In 2012, authorities used 600 tons of limestone boulders to build an 800-foot-long underwater snorkeling trail over two acres on the south side of the Blue Heron Bridge. Six to ten feet deep and marked off from boat traffic by buoys, it's enough to be adventurous yet not too intimidating. The underwater rock trail was built with little ledges and crannies in which sea critters love to hide. On a calm day, you might encounter squid, octopus, spotted rays, tarpon, starfish, and even cute lil' seahorses. Free parking, outdoor showers, picnic tables, and a lifeguard make this a near-perfect place to while away a beach day.