The Connecticut Valley Historical Society, based in Springfield, was incorporated in 1876. The Society originally held its meetings and housed its collections in the Springfield City Library, until a museum building, known as the William Pynchon Memorial Building, was constructed, next to the Springfield Science Museum, in 1927. The Connecticut Valley Historical Museum, designed by the Springfield architect Max Westoff, is a Colonial Revival structure, based on a the Colonial homes of the Connecticut River Valley. The main entrance of the museum, with its broken scroll pediment, is modeled on such homes as the Samuel Porter House in Hadley and the Josiah Dwight House, originally built in Springfield and later moved to Deerfield. The Historical Museum formally joined the Springfield Museums Association in 1948.