PORTLAND — The U.S. Postal Service says the Sherman Post Office will offer a special pictorial postmark to commemorate the northern Maine town’s 150th anniversary.

On Labor Day, Sept. 3, from 11 a.m. to 2 p.m., a postal booth will be set up at the Molunkus Lodge at 2 Church St.

Postmaster William Mehrhoff and his staff will stamp letters and postcards with a unique postmark documenting the event. Specially authorized by the Postal Service, the special postmark serves as an inexpensive souvenir of the occasion.