Activity for Hydenâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Answer | — |
A: Expanding occupied underground habitations safely? According to Wikipedia: "A cave-in is a collapse of a geologic formation, mine or structure which may occur during mining or tunneling. Geologic structures prone to spontaneous cave-ins include alvar, tsingy and other limestone formations" You can safely assume that you don't want to dig throug... (more) |
— | almost 9 years ago |