Related Clues:

• Spelunking venues
• Troglodyte homes
• Perhaps warning of hail in there
• Collapses, with ''in''
• Spelunkers' hangouts
• Bats' hangouts
• Gives in under pressure
• Spelunkers' haunts
• Capitulates
• Sites for stalactites
• Gives in, so to speak
• Grottos
• Bedrock dwellings
• Old painting sites
• Bat abodes