The Urban Rowhouse is an historic rowhouse 40–48 Pearl Street in Cambridge, Massachusetts. The rowhouse was constructed in a Second Empire/Mansard style in 1875, and is a contrasting example to the rowhouse on the adjacent block to providing further construction density in an urban setting. This rowhouse is of wood-frame construction, while the neighboring one is built of brick. The polygonal bays rise to the mansard roof, where the shape of the bay is continued, giving visual texture to the structure.