Windley Key Fossil Reef Geological State Park, a former quarry, offers a glimpse into the Florida Keys' history. Henry Flagler's Overseas Railroad, built in the early 1900s, relied on its limestone. Later, the quarry yielded polished “keystone,” a decorative limestone unique to this area until the 1960s. The Hurricane Monument in Islamorada, at Mile Marker 82, is constructed from keystone extracted here.
The park features several short loop trails throughout the grounds, where you can view the exposed fossilized coral reefs and remnants of the original quarry equipment. There is a drinking fountain, restrooms, and a lovely bench, perfect for a place to take a break under a canopy of hammock trees.
The park is open daily from 8 am until sundown, with a $2.50 entrance fee. The visitor center operates Thursday–Monday, 8 am to 5 pm.