Cumston Hall was built as the Town Hall and the Library in Monmouth. Harry H. Cochrane completed the plans in March 1899. The formal dedication took place on June 27, 1900.

It now serves as the Monmouth Theater and Town Library.

It was the first building in Monmouth to be lighted by electricity and was designed with its own private plant, supplied with power by a shinglemill.

The small building on the left was designed as the Selectmen's office. Next is the carriage porch. The architecture is a blend of Romanesque and Renaissance. The windows are leaded stained glass. The tower encloses the staircase leading to the second floor opera house.

Harry H. Cochrane, who designed the building, was not an architect, yet his plans were so thorough, barely any changes were necessary. Cochrane may have taken this photograph.