It was established in 1895, and the main building on its campus is listed on the National Register of Historic Places.

That facility was repeatedly enlarged, until 1889, when it was determined to no longer be feasible to expand it further.

The centerpiece of the campus is a sprawling, connected multi-building complex, at whose center is the hospital's first building, designed by the noted Portland architect John Calvin Stevens and completed in 1897.

The wings, which were designed by Bangor architect George Coombs, were added in 1899–1901, when the facility formally opened its doors.

The center's campus is located on Bangor's east side, between State Street (United States Route 2) and Mount Hope Avenue, with Saxl Park on its west side.