Park Key is an uninhabited island in the lower Florida Keys

Florida Keys

The Florida Keys are a coral archipelago in southeast United States. They begin at the southeastern tip of the Florida peninsula, about south of Miami, and extend in a gentle arc south-southwest and then westward to Key West, the westernmost of the inhabited islands, and on to the uninhabited Dry...

 about 14 miles east of Key West

Key West

Key West is an island in the Straits of Florida on the North American continent at the southernmost tip of the Florida Keys. Key West is home to the southernmost point in the Continental United States; the island is about from Cuba....

. It is 1500 Meters long, and between 75 and 260 Meters wide (190 meters on the average). It measures 28,5 hectare

Hectare

The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

s in area.

It is an island made from fill, so the railroad and later the road bed could be laid down.

U.S. 1

U.S. Route 1 in Florida

U.S. Route 1 in Florida runs along the state's east coast from Key West to its crossing of the St. Marys River into Georgia north of Boulogne, and south of Folkston. US 1 was designated through Florida when the U.S. Highway System was established in 1926.US 1 runs in the state of Florida, and...

 (or the Overseas Highway

Overseas Highway

The Overseas Highway is a highway carrying U.S. Route 1 through the Florida Keys. Large parts of it were built on the former right-of-way of the Overseas Railroad, the Key West Extension of the Florida East Coast Railway. Completed in 1912, the Overseas Railroad was heavily damaged and partially...

) crosses Park Key at approximately mile marker 18, between Lower Sugarloaf Key

Lower Sugarloaf Key

Lower Sugarloaf Key is the lower arm of an island known as Sugarloaf Key in the lower Florida Keys about 13 miles east of Key West.U.S. 1 crosses the key at approximately mile markers 16.5–17.5. Due to the routing of U.S...

 and Sugarloaf Key

Sugarloaf Key

Sugarloaf Key is a single island in the lower Florida Keys that forms a loop on the Atlantic Ocean side giving the illusion of separate islands. Although frequently referred to simply and with technical accuracy as "Sugarloaf Key", this island contains two distinct island communities, known as...

in the middle of Upper Sugarloaf Sound. It serves only as a causeway and is uninhabited.