Summerseat is a stately Georgian mansion built in what now is Morrisville. Although the sign in front says it was built by Thomas Barclay it was actually built by Adam Hoops, a wealthy Philadelphia businessman. Barclay was Hoops son in law and he gained possession some time later. When it was built in the 1760's, the home was on a parcel of land that extended to the Delaware River, a half-mile away. Only the front facade was brick.
The house has had numerous homeowners, including Robert Morris and George Clymer, both signors of both the Declaration of Independence and the Constitution. In December of 1776 George Washington used Summerseat as his headquarters just previous to his famous crossing of the Delaware River a few miles north.