Related Clues:

• Coral structure
• Beach locale
• Lagoon enclosure
• Ringlike coral reef
• Christmas Island, for one
• Coral isle
• Island surrounding a lagoon
• Lagoon border
• Reef in a ring
• Castaway's site, perhaps
• Key ring
• Lagoon formation
• 6-Down is part of it
• Lagoon former
• Reef around a lagoon