# Blue John Cavern

- **Country:** United Kingdom
- **Geology:** Blue John
- **Location:** Castleton, Derbyshire, England
- **Photo Caption:** Blue John seams in the cavern
- **Entrance Count:** 1

The Blue John Cavern is one of the four show caves in Castleton, Derbyshire, England. The others are Peak Cavern, Treak Cliff Cavern and Speedwell Cavern.

![Photo of Blue John Cavern](https://upload.wikimedia.org/wikipedia/commons/c/cf/Blue_John_Veins_in_the_Blue_John_Cavern.jpg)

**Source:** https://en.wikipedia.org/wiki/Blue_John_Cavern (Wikipedia, CC BY-SA)