Second Bank of the United States (420 Chestnut St.) 
The Second Bank of the United States, at 420 Chestnut Street, was designed by architect William Strickland and built between 1819 and 1824 at the cost of nearly half-a-million dollars. Modeled after the Parthenon in Athens, this temple structure is one of the finest examples of Greek Revival architecture in the United States. The huge building, measuring 86' x 140' with 16' x 10' porticoes at the north and sooth ends, contains 11,954 square feet of interior space. The main or north entrance is approached by a flight of marble stairs to a portico with eight large fluted Doric columns, 4' 6" in diameter, and a full Doric entablature. Coursed ashlar marble covers the three-story walls and the gabled roof is copper.
Strickland's design elevated the main floor of the bank building 9 feet above ground level and set the building off by a 14-foot-wide flagstone terrace 3 feet higher than street level. The central doorway at the main or Chestnut Street entrance opened to a vestibule with a paneled dare. On the "right and left" were large offices and directly ahead a central lobby or hallway leading to the banking roan which occupied the center of the building. Beyond, on the sooth end of the building, was the stockholders room, 23' x 50', and on either end of it, committee roans and marble stairways to the second story which was reserved for various offices.
The banking room, the heart of the Second Bank of the United States, retains many of its original architectural elements. The large 48' x 81' space still is divided by two rows of six fluted marble columns in the Ionic Order, which support three vaulted (arched) ceilings, the central of which is semi-cylindrical, 28' in diameter and 81' in length. Palladian windows give light to the room from the east and west.
The Second Bank of the United States first established itself in Carpenters' Hall in 1817, after Congress determined that a federal bank might spare the country a repeat of the financial crisis the country experienced during the war of 1812. When the magnificent marble temple was completed for the bank's use in 1824, Nicholas Biddle was serving as its president. Under his dynamic leadership the bank achieved its greatest influence and its Greek Revival design provided a model for numerous branch banks throughout the country. But active jealousy of the bank's power led to its downfall in 1836, when, following the determined leadership of President Andrew Jackson, Congress allowed the bank's charter to expire. The Commonwealth of Pennsylvania granted a charter to Nicholas Biddle for a state bank in its stead. When it failed in 1841, the Port of Philadelphia took over the building as the Custom House, in which use it continued until 1934, when a new Custom House reached completion on the next block. Subsequently a movement to preserve the Second Bank building resulted in its designation in June 1939 as a National Historic Site.
During the 1940s measured drawings and partial restoration of the building were completed under the direction of the Historic American Buildings Survey and the National Park Service. Many of the window openings added to the building during the years after the bank closed were covered over, and the original terracing at the front entanceway was reinstated. The interior restoration focused on the entrance lobby, as the main banking roan and side offices fortunately survived in their original appearance. The building presently houses the Independence Park Portrait Collection.