Driving the Byway
Begin the byway south of Florida City on US-1 as you leave the mainland. Continue on US-1 from Key Largo to Key West.
The byway, also known as the Overseas Highway, is lined with milemarkers every mile, like most every other highway in America. Awareness of these markers is useful as residents of the Keys refer to them continually. When asking for directions in the Keys, the answer likely will be that the spot being sought is at, just before or just beyond a mile marker number.
The GPS coordinates for the FKSH are as follows: the Northern limit is Latitude: 25 degrees 19.139 and Longitude: 80 degrees 38.722. The Southern limit is Latitude: 24 degrees 32.794 and Longitude: 81 degrees 47.849.