The riprap on which the castle of Saint-Ilpize rises is a volcanic structure highlighted by erosion. Geologists differ on its name, hesitating between the terms dyke or neck.
Open
Opening
| From January 01 to December 31 | |
| Monday | Open |
| Tuesday | Open |
| Wednesday | Open |
| Thursday | Open |
| Friday | Open |
| Saturday | Open |
| Sunday | Open |