Yoon S. Byun/Globe Staff
Somerville will hold its annual "Grand Union Flag Raising" on New Year's Day, featuring a processional led by a reenactor portraying General George Washington on horseback, according to announcement from the city.
The procession will leave City Hall at 11:30 a.m. and arrive at Prospect Hill Park at 12 p.m. The celebration commemorates the raising of the the first official flag of the United States atop Prospect Hill on New Year's Day in 1776.
Members of the public are invited to participate, and are encouraged to wear traditional colonial clothing, the announcement said.