Related Clues:

• Snorkler's interest
• Snorkeling spot
• Mariner's peril
• Diver's place
• Site of a wreck, perhaps
• Where a yacht might run aground
• Ocean obstacle
• Sea hazard
• Snorkeling destination, perhaps
• A kind of knot
• Boating hazard
• Great Barrier, e.g.
• Aquanaut's workplace, perhaps
• Submerged habitat
• Site of a shipwreck, perhaps