The key is home to Theater of the Sea, a popular tourist attraction since 1946.

[1] It also contains a Florida State Park Service geological site, and the popular Holiday Isle resort.

Prior to the building of the Overseas Railroad, the site consisted of two separate islands known as the Umbrella Keys.

Railway construction required the intervening space to be filled; it then became known as Windley Key, after an early settler.

Several quarries operated there for many years, supplying building stone locally known as "keystone".