Erwinna is an area where single family homes (sold over the past decade or so) have median property size of more than 3.5 acres. While there are $ million-plus estates, one still can find more modest accommodations on larger lots for "relatively" (note the quotes for emphasis) valued cost. Homes are older, with a median age of approximately 60 years, more than 3-times that of many other areas of the county.
The London Ferry operated here, across the Delaware, from 1699 to 1761. In 1769 one Colonel Arthur Erwin purchased more than 500 acres. He served in the Revolutionary War and was considered a colorful figure in his day. He was murdered by an angry squatter when visiting some landholdings in New York. The village name was changed from London Ferry to Erwinna (in honor of the Colonel) sometime around 1807 when the first post office was established. Hugh Erwin was the first postmaster, and was succeeded by one Joseph Erwin.
During the heydey of the Delaware Canal, Erwinna prospered as a center for boat building.
Erwinna's namesake covered bridge is the shortest of those in Bucks County. It's a lattice construction bridge, built in 1832 across Lodi Creek.