A little known United States federal agency called National Geodetic Survey, formerly (U.S. Coast and Geodetic Survey), defines and manages a national coordinate system, providing the foundation for transportation and communication; mapping and charting. Survey markers are the foundation for todays must have electronic navigational device called GPS.
Survey markers, also called geodetic marks or benchmarks, are objects placed to mark key survey points on the Earth’s surface. Today, the most common survey marks are cast metal disks stamped with legends on their face (seen above) set in rock ledges, sunken into the tops of concrete pillars (seen below), or affixed to the tops of pipes. The front of the faded concrete marker below reads “United States Coast And Geodetic Survey Basic Benchmark”.
This particular survey marker states that this Key West location is exactly 14.524 feet above sea level. It also reads that you can be fined up to $250 for tampering with or defacing this marker. You can find this geodetic marker directly in front of the Monroe County Courthouse beside this picnic table in the heart of Old Town.
PS – Just wait until you see where one is located at further up the Keys… it’s the ONLY one in the entire USA in such a location, so stay tuned! 🙂