Powder House Square

Powder House Square is a neighborhood and landmark rotary in Somerville, Massachusetts, United States. It is also known locally as Powder House Circle. It is the 6-way intersection of College Avenue, Broadway, Warner Street, and Powder House Boulevard. Powder House Square stands at the southern tip of Tufts University's main Somerville/Medford campus, and borders the northern edge of Nathan Tufts Park. The square takes its name from the 18th century Powder House which overlooks the rotary from Nathan Tufts Park.

Powder House Square was home to one of the first hostile acts of the American Revolutionary War. The removal of colonial gunpowder by British soldiers, and the massive popular reaction known as Powder Alarm that ensued, are considered to be a turning point in the events leading up to war.