It was the capitol from 1842 to 1845. Washington was the first county seat of Washington County in 1836. Today there's not much there except the park. The house where the Declaration was debated and signed is an authentic recreation. The architect located the original footers and used contemporary accounts for the exterior.
Most accounts mention the cold and lack of window panes.
The delegates ended up tacking cloth over the openings. The Convention has to be seen in the context of Santa Anna's invasion. The Mexican Army closed on the Alamo on February 23. Another factor urging action on the Convention was the inhospitable nature of Washington. The town was notable as a kind of Texas-style crossroads.