Ridgefield Center Historic District
The Ridgefield Center Historic District was listed on the National Register of Historic Places in 1984. Portions of the content on this web page were adapted from a copy of the original nomination document. [†] Adaptation copyright © 2010, The Gombach Group.
The Ridgefield Center Historic District occupies approximately 395 acres of the most densely built up part of the Town of Ridgefield, around the activity center, which is south of the geographic center of the town. The district includes about 312 principal structures, 30 from the 18th century, 125 from the 19th century, and 157 from the 20th century. All but 67 are considered to contribute to the architectural and historical significance of the district. Most of the 67 non-contributing structures are less than 50 years old. There are ten vacant lots. The 312 principal structures include civic and commercial buildings on the main street, churches, Colonial and Greek Revival houses of modest size, large Victorian country homes and late-19th century workers' homes that together form streetscapes of varied but harmonious interest.
The location and topography of Ridgefield were important to the architectural development of the Ridgefield Center Historic District. Its position on the western edge of Connecticut, 15 miles above Long Island Sound and seven miles below Danbury, was out of the way, and it never became a trading or manufacturing center. The terrain is dominated by parallel north-south ridges that tend to diminish the agricultural value of the land. The principal streets of the Ridgefield Center Historic District run along such ridges, including Main Street, High Ridge Avenue, Prospect Ridge and East Ridge.
One of the oldest houses in Ridgefield is the Deacon Thomas Hawley House, c.1715, at 236 Main Street. It was built by the proprietors for the town's first minister, Thomas Hawley, who came from Northampton, Massachusetts. It has received recognition through being recorded by the Colonial Dames of America in the State of Connecticut, and, with measured drawings, by the Historic American Buildings Survey. Its gambrel roof and the slight flare of the eaves suggest Dutch influence from the Hudson River Valley. The present Georgian configuration of the house with central hallway and twin chimneys suggests that it has undergone extensive alterations, perhaps toward the end of the 18th century.
Another equally early structure is the Nathan Scott House at 5 Catoonah Street, moved in 1922 from its original location at the corner of Catoonah and Main streets, at which time it lost its fireplaces. The 12-over-6 sash of the second floor and the old, hand-split, 30" shingles are among its outstanding features.
A second minister's home (23 Catoonah Street), also moved to Catoonah Street from Main Street, is the former Episcopal Rectory, dating from 1790. It is a 5-bay, Georgian, hipped-roof house, with added 19th century porches. Catoonah Street, one block long in the center of town and lined with modest houses from the 18th, 19th and 20th centuries, is one of Ridgefield's most picturesque streets.
The Benedict House, c.1790, at 17 Main Street, is a more conventional Colonial house with central chimney, but again with shingles rather than clapboards. Its central chimney and fireplaces are intact.
35 Main Street, c.1740, with its flared eaves, is another example of Dutch influence. This structure originally was a store located behind 440 Main Street. It is one of the many early houses in Ridgefield that have been moved.
The Keeler Tavern, c.1760, at 132 Main Street, is famous not only for the part it played in the Ridgefield action when the British forces passed through in 1777, but also because it was purchased in 1907 by Cass Gilbert, the well-known architect, who made alterations and improvements as outlined more fully in the National Register nomination for the property.
149, 181 and 190 Main Street (c.1760, 1713, and 1787) are three more Colonial houses that have survived vicissitudes. Number 149 Main Street, possibly moved from across the street, has been joined to a Greek Revival style house; 181 Main Street has a Greek Revival addition and 1930s alterations; and 190 Main Street has been hidden from view behind a larger front addition.
All of these houses, and others, have accommodated to changing times and have survived. They are now an indigenous part of the streetscape successfully taking their places with later structures in a district made homogeneous in appearance through shared scale, massing and spacing of structures from three different centuries.
The first church to be built in the Ridgefield Center Historic District was the Congregational meetinghouse on the green (no longer extant) near the corner of Main and Market streets. When a second church building on this site was found to be inadequate, a new stone edifice was erected in 1888 at 99 Main St., the southwest corner of Main Street and West Lane, to the design of J. Cleveland Cady of New York, who was the brother of the minister.
Cady's church is an odd but successful amalgam of several styles. The basic plan and mass are those of an English Gothic parish church such as had been encouraged in mid-century by the Ecclesiological Society.
The high roof of the nave, lower ridge line and smaller mass of the chancel, square tower with turret at one corner located on the side, all are characteristics espoused by the Ecclesiologists. The pointed arches of the doorway, tower and chancel windows are in the Gothic mode. On this reasonably consistent basic form, lacking only the usual buttresses, Cady designed a Queen Anne, half-timbered gable in the roof of the nave, added his trademark of a secondary vertical line, here a chimney adjoining the tower, and constructed the walls of rough stone in the manner currently being popularized by H.H. Richardson. The American "Four Square" house next door and 20th-century parish house buildings are part of the church complex.
St. Stephen's Episcopal Church at 351 Main Street, by Kerr Rainsford in 1914, is the fourth structure on the site, following the first built in 1725, the second of 1785, and the third of 1841. Typical of its era, and well done, the present building is Georgian Revival in style, with Doric portico, tower and steeple. It is one of the few buildings in Ridgefield to use ashlar stone as a building material. The Episcopal Church has three frame houses on its property. The Parish House, 1916, is a Georgian Revival, twin-chimney, 5-bay, central-doorway, clapboard structure with round-headed windows in its dormers. North and South halls, both built at the turn of the century, are hipped-roof examples of the Neo-Classical and Georgian Revivals, both with flat-roofed porticos.
The Jesse Lee Memorial Methodist Church at 207 Main Street, by Harold Wagoner in 1965, is a later example of the Georgian Revival, executed in brick. The church has great verticality, created by the colossal columns supporting its pedimented portico and the spire that rises over an open belfry to a height of 149 feet. The church was constructed immediately in front of, and obscures the view from the street of, the Henry Hawley House (1895) that now serves the church as Welsey Hall. The Henry Hawley House is a 3-story, Tudor Revival, stone-and-stucco, half-timbered, twin-gable-roofed house with many excellent details. Windows are leaded stained glass, ceilings are pressed metal and there are carved mantels and newels of mahogany.
St. Mary's Catholic Church at the western end of Catoonah Street, by Joseph Jackson in 1896, succeeded an earlier frame structure that still stands at 13 (rear) Catoonah Street, now used for a commercial purpose but with the five lancet windows of its west elevation still in place. The present edifice is a Gothic Revival, brick structure with clapboards covering the recessed gable end. A square tower, shingled, with turrets and a tall pyramidal roof, brownstone dripstones over the windows, clerestories and buttresses, are other Gothic features. A companion rectory that stood on the same property has been demolished, but its carriage house survives as does the sexton's house at 184 High Ridge Avenue and the Parish House at 52A Catoonah Street. All of these secondary buildings still have their original ochre-and-brown colors. Each of these four churches is the centerpiece of a cluster of historic buildings.
The number of country homes built in the fourth quarter of the 19th century when Ridgefield became popular as a country retreat is not recorded, but it surely ranges into the dozens. Many of them were built on High Ridge Avenue, west of Main Street, and on East Ridge and Prospect Ridge, east of Main Street. Not all of them survive; for example, the Newbold Morris House at 23 High Ridge Avenue, has been replaced by a 1946 Georgian Revival, brick, H-shaped house with Doric columns. Two houses on High Ridge Avenue were built by New York publishers. The E.P. Dutton House, c.1890, at 63 High Ridge Avenue, combines Queen Anne shapes with a gambrel roof and other Colonial Revival features, and a cobblestone wrap-ground porch. The house is covered with shingles. This siding and the plastic mass of the roof with the rounded porch reflect strongly the influence of the Shingle style, of which there is, surprisingly, no pure example in Ridgefield. Henry Holt at 87 High Ridge Avenue, facing Peaceable Street, c.1890, built a 3-story, Georgian Revival brick house with all the popular millwork, including a central pavilion with modillions and dentil course and a Palladian window over a bowed, columnar porch.
Four large houses on the east side of East Ridge, south of Governor Street, were built in the 1880s and 1890s, three in the Queen Anne style and one in the Neo-classical Revival style. All of frame construction, they are covered with clapboards and fish scale shingles, their gables and turrets expressing the fanciful designs of the unknown architects. Number 56 East Ridge, the Neo-Classical Revival house, like Governor Loundsbury's mansion at 316 Main Street, was patterned after the Connecticut building at the World's Columbian Exposition. The Queen Anne house at 72 East Ridge is now adaptively used as the Ridgefield Police Headquarters.
On Prospect Ridge to the east, a 3-story, Queen Anne house of stone is dominated by a 3-1/2-story, round, corner tower with conical roof. The medieval castle keep atmosphere of this house is enhanced by the Neo-Jacobean strapwork and oak-coffered ceilings of the interior. The house is now adaptively used as the offices of the Board of Education.
The site of one of the large homes, now demolished, developed at this time on Main Street at the corner of Gilbert Street was given to the town and is now Ballard Park. The estate's granite ashlar stone wall with iron picket fence survives. The town has elected to devote a portion of the park to elderly housing. Another gift to the town at the turn of the century was the Elizabeth W. Norris Building, across from the park, 1901, Raleigh W. Gildersleeve, architect, for the Ridgefield Library and Historical Association. It is a 1-story, Second Renaissance Revival, standing-seam, hipped-roof building of brick and limestone. Having rustication, consoles, key blocks, modillions, and antifixae, this building is of more architectural pretension than most in Ridgefield.
Construction of the new, large houses required construction crews, and once completed the new places needed maintenance and service. The infrastructure of the town had to be expanded to adjust to the new situation. These job opportunities drew immigrants to Ridgefield, mostly from Ireland and Italy. Housing for the new workers grew up in the northwest corner of the Ridgefield Center District along Gilbert Avenue, Abbott Avenue, Bryon Avenue, Barry Avenue, Greenfield Avenue, and Fairview Avenue. These small frame houses remain in place today in their original relationship to one another, well maintained, displaying turn-of-the-century vernacular architecture.
In addition to the expected modest examples of contemporary architectural styles, including Colonial Revival and late Queen Anne, two less usual expressions of architectural design are found in these workers' houses. One is the Japanese influence seen in the projecting front gable of 22 Fairview Avenue. This prominent gable with bracketed eaves reflects first the Bungaloid style developed in California, but also includes reference to the Japanese antecedents of the California Bungalow. The Japanese elements are the flared eaves and the battered sides of the gable. Similar gables are found at 25 Fairfield Avenue, 22 Bryon Avenue and 85 Main Street.
The second unusual expression is the stucco, concrete and tile house at 29 Abbott Avenue, c.1930, attributed to a mason of Italian origin who worked in the materials traditional to his trade. The balustrade that once ran between the concrete piers on his porch roof now is missing. The older and larger house at 32 Gilbert Street, known to have been built by Aldo Bacchiochi, Sr., used the same masonry materials.
Public and Commercial Buildings
The small, 1-story, frame, commercial building with vertical siding and stepped parapet at 3 Catoonah Street probably is representative of modest structures used as stores and shops in the 19th century. It is the last of its kind in Ridgefield. A disastrous fire in 1895 destroyed ten buildings near the intersection of Catoonah and Main Streets, clearing away other structures that may have resembled 3 Catoonah Street, and explaining why so many of the buildings in this area were built at the turn of the century. Chief among the replacement structures is the Bedient Block at the northeast corner of Main Street and Bailey Avenue, a frame Queen Anne structure with square, 4-story tower. Two earlier Queen Anne houses, both with towers, at 396 Main Street and 409 Main Street survived the fire and have been adapted to commercial use. Number 381 Main Street, dating from after the fire, is a Neo-Classical Revival frame structure carried out in country fashion with a curvilinear pediment.
Other buildings in the central grouping are more sophisticated. The Town Hall, 1896, by Philip Sutherland, a typical brick, Georgian Revival, hipped-roof structure is of interest because its millwork, including modillion blocks and fanlight, originally was painted brown. The 1908 Georgian Revival firehouse around the corner at 6 Catoonah Street was treated in similar manner, making the two companion pieces.
Two bank buildings south of the Town Hall add distinction to the streetscape. Well detailed, the Union Trust Company, 1907, by Ernest Green, is a Neo-Classical Revival design distinctive for the two round-arched openings that dominate its facade. One of these openings is the front entrance, the other a window. The Ridgefield Savings Bank, 1930, by Ralph Hawes and Ernest Strassie, is a surprise in conservative, country Ridgefield because its design is an Art Moderne treatment of the Greek Revival. Two colossal, Ionic columns are set in antis between piers with rounded corners that carry up through the attic. The rounded corners coupled with treatment of the piers and attic as flat planes create a streamlined effect. The front wall behind the columns is glazed in a bronze frame, in classical detail.
The distinction of the architecture in the Ridgefield Center Historic District arises both from the excellence of individual structures and from the panoramic streetscapes that are composed of many buildings constructed over a period of three centuries. Colonial homes, Greek Revival structures, buildings constructed in 19th century picturesque styles, workers' homes from that era and early-20th century examples exist side by side, in their original relationship to one another, providing an excellent visual summary of the history of American architecture in a country town.
The density of development in Ridgefield was low for 2-1/2 centuries. After being settled in 1708 and designated a town by the General Assembly in 1709, the population increased by 1750 to 2000. Two hundred years later, in 1950, it has increased only to 3000. From 1950, however, Ridgefield has participated in the development that has occurred in southwestern Connecticut due to the outward expansion of suburban New York and the relocation of business headquarters from New York City. Ridgefield's population in 1975 was 22,000. The many older structures that remain standing in the Ridgefield Center Historic District have now been joined by new buildings. The affluence of the community is reflected in the character of the new homes and shops. Also, many older buildings have been rehabilitated in recent years. It is the Ridgefield Center Historic District's 18th-, 19th- and 20th-century houses, churches, commercial structures and other buildings that are the subject of this nomination.
As usually was the case in Colonial Connecticut's interior towns, the original settlers apparently were drawn to Ridgefield by the prospect of land for farming, although the rugged topography of the ridges limited the desirable agricultural land to valleys between the ridges. The first houses and first church were built in the Ridgefield Center Historic District along the ridge that became Main Street, approximately between Market Street and Rockwell Road. Although the present edifice of the Congregational Church now is at another location, the home built for the first minister still stands on its original site, looking very much at ease in the 20th century. Other houses and shops were built close together along this section of Main Street near the meetinghouse, and, more widely dispersed, throughout the district as the land was settled.
The thirty houses in the Ridgefield Center Historic District from the 18th century are an integral but less-than-dominating part of the streetscape as they are outnumbered by later structures. Because of these 18th-century houses, the appearance of the district reflects the great age of the community as an important component in the successful interrelationship of the older and newer structures that now exists.
The initial pattern of limited development continued through the 18th century and through the first half of the 19th century. The 19th-century industrial revolution passed Ridgefield by. There was little in the way of events that had impact on the Ridgefield Center Historic District's building pattern until after the Civil War when Ridgefield became popular as a place for summer homes. Large houses were built along the ridges by summer people from New York and other cities. Development of the town as a resort required a service infrastructure that gave employment to artisans and workers whose smaller, vernacular homes add still another dimension to the architectural make-up of the streetscapes.
During the 19th century there was some light industry in the Ridgefield Center Historic District, notably the manufacture of carriages and shirts. As railroads were built in the river valleys, communities at higher elevations, such as Ridgefield, did not participate in Connecticut's 19th-century industrial development.
By the end of the 19th century, the activity center had moved a block or two north on Main Street to the corner of Catoonah Street. A disastrous fire there in 1895 occasioned the construction of a new Town Hall and other nearby buildings. More recently, mid-20th century development pressures have led to construction of many large new homes and some smaller ones and some multiple-unit housing included in the district, and other apartment buildings and commercial structures that are excluded.
The styles of architecture that predominate in the Ridgefield Center Historic District are related to the two important building periods, Colonial and post-Civil War. There are many houses built in the 18th and early 19th centuries, but few Greek Revival, Italianate, Gothic Revival or Second Empire style structures such as were built elsewhere during the decades before the Civil War when there was little construction in the district. The Queen Anne style of architecture, popular after the Civil War, is well represented although the Stick style and Romanesque Revival, curiously, are missing. Colonial Revival and Georgian Revival style structures from the turn of the century are well represented.
The Ridgefield Center Historic District's 18th-, 19th-, and 20th-century houses, churches, civic and commercial structures, built side by side and representing various types, ages and styles, are sensitive to one another in scale and setting and form a cohesive district of discrete components.
The buildings of the Ridgefield Center Historic District span three centuries in time and a full range of American architectural styles from the Colonial through the Art Moderne. The buildings, most of them of frame construction, relate well to one another in terms of size, scale, materials and spacing and are significant for their integrity and lack of intrusions.
The Ridgefield Center Historic District enjoys a wide diversity of building types, styles, and functions. Some of the 18th century houses are Colonial in plan, with central chimney; others are Georgian, with central hallway, both constructed using the post-and-beam, mortise-and-tenon method. Gable roofs and flared gambrel roofs are represented. Early 19th-century houses continued the 18th century method of construction in the Greek Revival style. As the 19th century wore on, a wider range of architectural styles was introduced. The Queen Anne style houses on Main Street and elsewhere are excellent examples of their types, and one of the summer places (63 High Ridge Avenue) approaches the Shingle style. The high style influence of professional architects is seen in the two 19th-century churches, Romanesque Revival at the Congregational Church and Gothic Revival at St. Mary's Church.
With the approach of the 20th century, the diversity of residential architecture was further increased in both style and scale. The classic revival trend was represented by Governor Lounsbury's mansion and the Maynard House, among others, while, simultaneously, smaller scale vernacular houses were built along Bryon, Fairview and Greenfield avenues, most of them still standing.
After the serious fire at the center of the Ridgefield Center Historic District in 1895, two public buildings, the Town Hall and Firehouse, were designed in the Georgian Revival style of the period, while the 1901 library is a more sophisticated exercise in the Second Renaissance Revival mode. The former high school, Georgian Revival in design, is the largest building in the district. The Art Moderne bank, somewhat unexpected in a country town, adds one more interesting style to the wide diversity of architecture in the district.
The 18th-century houses of Ridgefield were constructed of timbers using the usual post-and-beam and mortise-and-tenon method, with rooms disposed around a central chimney. As compared with other Connecticut towns, two characteristics in Ridgefield were somewhat different. First is the presence of the gambrel roof with flared eaves, reflecting Dutch influence from the Hudson River Valley. The importance of this influence in Connecticut tends to decline in the central and eastern parts of the state. Second, many of the Ridgefield houses have shingled siding instead of clapboards. While there are no statistics at hand, it seems that the proportion of shingled houses in Ridgefield is larger than usual.
An unusual feature of the history of buildings in Ridgefield is that there has been so little demolition. Redevelopment has yet to reach Ridgefield. Instead, due to the slow pace of development for 2-1/2 centuries, there has been little pressure to replace existing buildings with new buildings. Consequently, structures from the 18th, 19th, and 20th centuries exist side by side. Many of the original Colonial farm houses are still in place, now with 19th and 20th century neighbors. This mix of styles and periods is unusual and presents a valuable panorama of styles in a limited geographical area.
A positive force working to sustain the integrity of the Ridgefield Center Historic District was the fact that it offered few incentives for industrial or commercial development during the 19th century and first half of the 20th centuries. It had no natural resources and its location, not on any major transportation arteries, was negative for development as a trading center. The great industrial revolution of the 19th century, based on steam power and railroad transportation, was not attracted to the district. Instead Ridgefield was one of the communities, located at relatively high elevations where rushing streams provided the waterpower essential to early industry, that tended to lose their industry to the river valleys where railroad construction was easier. The gristmills, tanneries, foundries, cooperage shops, needle trade and carriage manufacturing that did exist in or near the district early in the 19th century gradually diminished and died out as industrial development descended from the ridges to the river valleys. This was all to the good in terms of historic preservation, and is an important factor in explaining the survival of so many 18th- and 19th- century houses in the district.
The post-Civil War popularity of Ridgefield as a country retreat, its high ridges now an important asset, brought the first real changes in the town's, physiognomy in 250 years. For the first time, many new buildings were built. Again, as there have been no subsequent developments of note, until the last several decades, many of the post-Civil War large homes, fortunately remain standing.
The new large houses were entirely different from anything that had preceded them larger, more pretentious, built at greater cost, and lived in by affluent families who were not dependent on the Ridgefield economy for their income. While these houses were large enough and fine enough, in all probability, to be designed by architects, regrettably the identities of the architects are known for very few of them.
The few instances of known work by important architects in Ridgefield usually are explained by personal associations. For example, J. Cleveland Cady was the brother of the minister of the Congregational Church he designed. Cass Gilbert altered and enlarged the Keeler Tavern because he owned it. In other instances the names of the architects occasionally are known, as Joseph Jackson for St. Mary's Church, Ralph Hawes and Ernest Strassie for the Ridgefield Savings Bank and W. Kerr Rainsford for St. Stephen's Episcopal Church. Their work is of interest, but little is known about the men and their careers. In the majority of instances for the big houses along High Ridge Avenue, Main Street, East Ridge and Prospect Ridge the architects simply are unknown.
The Ridgefield Center Historic District's architecture reflects the four phases of the community's historical development. The first phase was the early-18th century settlement situated along Main Street that is still identified by buildings such as the Deacon Thomas Hawley House (1715) at 236 Main Street and its contemporary neighbor across the street at 181 Main Street as well as the Keeler Tavern (1760) at 132 Main Street. The majority of the district's thirty 18th-century houses were in place along Main Street at the time of the Revolutionary War skirmish of 1777 when General Tryon led his British forces along the street en route to Long Island Sound after raiding Revolutionary stores at Danbury. Three of the district's present-day churches also are on Main Street.
During the first half of the 19th century little development occurred. These decades were followed by the second period of active growth in the district as a resort community in the second half of the 19th century. The change in growth rate that occurred is vividly reflected in the number of structures in the district dating from the first and second halves of the century, 17 from the years 1800-1949 and the much larger number of 108 from the years 1851-1900. The second half of the 19th century saw the construction of the big country homes, concentrated along High Ridge Avenue on Main Street north of the Colonial settlement nucleus and on East Ridge. Outstanding examples from this second period include the Queen Anne house for E.P. Dutton at 63 High Ridge Avenue, the Georgian Revival mansion for Henry Holt at 87 High Ridge Avenue, Governor Lounsbury's Neo-Classical Revival mansion, 316 Main Street, and the large Queen Anne frame house at 62 East Ridge.
The third type of development was necessitated by the second. The advent of the big summer places required facilities and people to service the many large new structures and the infrastructures of the town that grew accordingly. Housing for this service component of the community was built in the northwest corner of the district along Gilbert Street and Abbott, Barry, Greenfield and Bryon avenues. These streets constitute a neighborhood, with a high degree of integrity, of houses built mostly in the 20th century before World War I, quite different from but necessary to the large homes on High Ridge Avenue, Main Street and East Ridge. Less sophisticated stylistically than the large houses, the smaller homes nonetheless have interesting features such as the craftsmanship of an Italian mason at 29 Abbott Avenue and the Japanese influence present in the gable of 22 Fairview Avenue.
The fourth component of Ridgefield Center's development is the civic and commercial buildings that from mid-19th century have been centered on the intersection of Main and Catoonah streets. The town hall, banks, lodges, shops and offices provide essential core services for the district as a whole in buildings of architectural interest. For example, the c.1900 frame, commercial building at 381 Main Street has a curvilinear pediment characteristic of the period and a row of unusual spool-shape pieces in lieu of a dentil course. The Bedient Building, 404 Main Street, represents commercial function in the Queen Anne style, while the Savings Bank at 374 Main Street is an unexpected and pleasing exercise in Art Moderne.
The four broadly-defined architectural components of the district's development relate well to one another in mass and spacing and continue visually to work together as elements of a vigorous community. Over the centuries, the early street pattern has been maintained. New buildings often have been infill structures, taking their places between the older buildings, respecting them and not becoming intrusions in the streetscapes. Exceptions have been some concrete block commercial buildings in the shopping center and groups of new homes built as developments. Fortunately, there are only two newly-developed streets in the district. Griffith Lane and Jackson Court, both developed on land that is between the main streets, leaving the principal streetscapes relatively unscathed.
Changes have occurred in the district, as must be expected. Many grand old houses have undergone damage by fire or insensitive alterations to their detriment, but have survived with significant historic fabric. The Ridgefield Center Historic District is unified by its position along the ridges, by mature landscaping and by the homogeneity of the mass and setting of the architecture. The alterations have for the most part been held within limits without ruining the historic ambiance of the village. Most importantly, the houses survive and work well with one another.
Bedini, Silvio A., Ridgefield in Review, Ridgefield, 1958.
Rockwell, George L., The History of Ridgefield, Connecticut, Ridgefield, 1927.
† David F. Ransom and John Herzan, Connecticut Historical Commission, Ridgefield Center Historic District, nomination document, 1983, National Park Service, National Register of Historic Places, Washington, D.C.