Fort Wool was the companion to Fort Monroe in protecting Hampton Roads. Originally conceived in 1817, Fort Calhoun was built on a 15-acre artificial island southeast of Old Point Comfort in Hampton, Virginia. Construction and repairs continued for decades, because the foundation was unstable. The first level of casemates was finished in 1830. Construction continued through the 1830's, when Andrew Jackson came to escape from the heat of Washington, D.C.

The Fort played a crucial role for the Union forces during the American Civil War, and it was renamed in honor of Union Major General John Wool.

The Fort was modernized in the early 20th century, and served as the part of the harbor's defense during World War I. The outmoded fort was finally abandoned by the military, but it remains a major draw for tourists. During the summer months, it is served by various harbor tour boats.