Broadway originally crossed the neck of land that linked Charlestown with the mainland. The oldest substantially unaltered house in Somerville, the Adams-Magoun House controlled a seventy-one-acre farm astride Broadway. The house faces south, with its gable roof oriented toward the street, although it is now hemmed in by buildings and a busy thoroughfare. Joseph Adams, a relative of President John Adams, supposedly erected the house in 1783. The clapboards and windows with their projecting frames support this early construction date. However, other architectural features suggest the house may have been built at a somewhat later date—modified in the early nineteenth century. Pilasters and a pediment frame the doorway with its round-arched fanlight, a popular design featured in the builder's guides by Asher Benjamin, whose first publication appeared in 1797.