Blue Grotto

Blue Grotto is a spring-fed freshwater cavern and sinkhole with a large open basin that slopes into an overhead cavern. The site features crystal-clear water, large rock formations and ornamental statues (including a dolphin statue and "Castle Rock"), and resident softshell turtles such as the noted individual "Virgil." It is a controlled, widely popular training and recreational dive site. Entry is from a fixed shore platform; the basin is shallow around 40 feet and the cavern extends to about 100 feet. Permanent mooring lines, a fixed descent line and dive platforms at about 20 and 30 feet guide divers, and there is an underwater air bell near 30 feet. Visibility is exceptionally high, often 50–100 feet, but can drop if the basin is silted. Water temperature is steady at about 72°F year-round. The lower cavern becomes fully enclosed overhead; only certified divers may descend beyond the open basin, many operators require cavern or cave certification for deeper penetration, solo diving is not permitted, breath-hold diving requires permission, and technical configurations (doubles, rebreathers, sidemount) are used for training and deeper dives.