The Whaleback light is located at the northeast side of
Portsmouth Harbor, although it is in Maine waters. The 48-foot stone tower
was completed in 1831, and a fourth-order Fresnel lens installed in 1855.
1859 saw a fog bell added.
In 1872, a new 75-foot tower was built of granite blocks.
Part of the old tower still remains. The light was automated in 1964, and
the Fresnel lens was replaced by a modern optic.