Most of the buildings lining Main Street today date to the 19th century. Periods of heightened building activity include the decade following 1800 and the 1830's. As in many downtown areas, fire loss has had an important role in the evolution of Main Street. In 1842, a fire set by a prisoner in the jail swept away everything from Depot Street south to and including the Meeting House which previously stood on the site of the South Parish Church. Concurrent with this period of accelerated building activity in Charlestown was the flourishing of the Federal, Greek Revival and Gothic styles. Local master builder Stephen Hassam (1761-1861) appears to have acted as one of the primary vehicles for transporting all of these styles to Charlestown and is responsible for the delicate woodcarving adorning many Charlestown buildings. Born in Boston in 1761, Hassam spent his early years as an apprentice to a clockmaker in Worcester, Massachusetts. By 1778 he was in Charlestown, the earliest structures by his hand reportedly date to 1800. An exact source for Hassam's architectural training is not known though he was clearly heavily influenced by the architectural guides of Asher Benjamin and his contemporaries. Buildings within the district attributed to Hassam include the old Connecticut River Bank, South Parish Unitarian Church and numerous private residences. - NRHP, 10 June 1987