A sudden squall could drive a ship westward off its southerly Gulf Stream route from Liverpool, England to New Orleans, Louisiana and onto a massive coral reef in the shallow seas along the Florida Keys, where sailors faced a cracking hull, rising water, darkness, and stormy seas with no rescue because no one knew they were in peril. For centuries, such shipwrecks were common there, and wreckers sailed out at dawn to search for survivors and salvage, making shipwreck salvage a mainstay economy from Key West to Miami. To reduce these losses, aids to navigation were built over generations, including the Totten Beacons designed by U.S. Army Officer Lt. James Totten in the mid-1800s, which were originally intended for chart-making but were soon used as unlit visual guides by sailors. Because ships still needed a marker visible far out in the ocean by day and night, the Fowey Rocks Lighthouse was built in 1878 and drilled into the ocean floor near Totten Beacon "P"; five more like it span the Florida Keys. Modern technology has largely ended shipwrecks in the region and the wrecking industry has passed, but the Fowey Rocks Lighthouse remains an important functioning aid to navigation, while six historic shipwrecks and the lighthouse form a protected Maritime Heritage Trail visited for snorkeling and SCUBA diving.