Fort Pickens was the largest of a group of forts designed to fortify Pensacola Harbor. Constructed
between 1829-1834, Pickens supplemented Fort Barrancas, Fort McRee, and the Navy Yard. Located at
the western tip of Santa Rosa Island, just offshore from the mainland, Pickens guarded the island
and the entrance to the harbor.

During the late 1890's and early 1900's, new gun batteries were constructed at Fort Pickens. On
June 20, 1899, a fire in Fort Pickens' Bastion D reached the bastion's magazine, which contained
8,000 pounds of powder. The resulting explosion killed one soldier and obliterated Bastion D. The
force of the explosion was so great that bricks from Bastion D's walls landed across the bay at
Fort Barrancas, more than one and one-half miles away.