| Clue | Source | Date |
|---|---|---|
| Cylinders of calcium carbonate projecting upward from a cave floor (11) | ||
| Nuisance at a POW camp? | Wall Street Journal | 24 Apr 2019 |
| Nuisance at a POW camp? | ||
| Prison kids? They may grow up in a dank environment | ||
| They're at the bottom of 37 Across | Newsday | 10 Feb 2017 |
| Cave formations | Thomas Joseph | 09 Nov 2015 |
| Features of some caves | ||
| Uppers? |