The Bulfinch Triangle Historic District is a historic district roughly bounded by Canal, Market, Merrimac, and Causeway Streets in the West End of Boston, Massachusetts. The entire district was laid out by architect Charles Bulfinch on land reclaimed from the old Mill Pond, and is now populated by well-preserved commercial buildings from the 1870s through early 1900s. It was added to the National Register of Historic Places in 1986.