The Overseas Highway, the southernmost leg of U.S. Highway 1 and sometimes called the Highway That Goes to Sea, is a modern wonder.
The road follows a trail originally blazed in 1912 when Henry Flagler extended his Florida East Coast Railroad from Miami to Key West. The railway ceased operation after severe damage to the infrastructure in a 1935 hurricane.
Construction of the highway began in the late 1930s. Its foundation incorporated some of the original railway spans as well as the coral bedrock of individual keys and specially constructed columns. Completed in 1938, the highway marked the beginning of an incredible adventure for the North American motorist.
The Overseas Highway represents an incredible engineering feat: 113 miles of roadway and 42 bridges leapfrogging from key to key in a series of giant arches of concrete and steel. In 1982, 37 bridges were replaced with wider spans, including the well-known Seven Mile Bridge at Marathon.
In 2002 the Florida Keys Overseas Heritage Trail was added, which includes the Grassy Key Bikeway. Spanning mile markers (MM) 54.5 to 58.5 bayside, the eight-foot-wide Grassy Key Bikeway is landscaped and furnished with a split-rail fence as well as bollards to prohibit automobile access.
The Heritage Trail is a paved recreational path along old Flagler railroad bridges and the Florida Department of Transportation right-of-way that features crossways between bayside and oceanside. Stretching from MM 106.5 to MM 0, the trail includes interpretive trailheads designating attractions and other public areas on and off U.S. Highway 1 - as well as benches, an art bicycle rack and a limestone column sign with an Overseas Heritage Trail map.
Today, the highway can be traversed by car in less than four hours from Miami. However, drivers should allow time to experience the natural beauty of the ever-changing scenery of the seas and wilderness bordering the roadway, and the magnificent sunrises and sunsets.