It is located at 92 Court Street in the center Machias, in an architecturally distinguished Romanesque Revival building, whose construction was funded by native son Henry Homes Porter.

[1] The library is located near the center of Machias's downtown area, at the junction of Court and Free Streets.

It has an T-shaped plan, the stem of the T paralleling Court Street, with gable ends facing to the north, west, and south, that are capped by Romanesque pinnacles.

The main entrance is in the northern corner of the T, sheltered by a portico with large round arches.

The present building was designed by Boston, Massachusetts architect George A. Clough and was completed in 1893.