Ordered by the number of climbs recorded. About volcanic tuff.
| Crag | Location | # Climbs |
|---|---|---|
| Smith Rock | United States / Oregon / Deschutes County | 23 |
| Kasagiyama | Japan / Gifu | 11 |
| Horai | Japan / Aichi | 11 |
| Whanganui Bay | New Zealand / Waikato Region | 7 |
| Pentire Point | United Kingdom / England / Wadebridge | 6 |
| Cam Crags | United Kingdom / England / Keswick | 4 |
| Tintagel North | United Kingdom / England / Tintagel | 3 |
| Ponderosa Boulders | United States / New Mexico / Sandoval County | 3 |
| Cwm Dulyn Boulders | United Kingdom / Wales / Caernarfon | 3 |
| Sad Boulders | United States / California / Inyo County | 3 |
| Tanygrisiau Boulders | United Kingdom / Wales / Blaenau Ffestiniog | 3 |
| Gibraltar Rock | New Zealand / Canterbury Region | 2 |
| Happy Boulders | United States / California / Inyo County | 2 |
| Moelwyn Bach | United Kingdom / Wales / Blaenau Ffestiniog | 2 |
| Barras Gug | United Kingdom / England / Tintagel | 2 |
| RAC Boulders | United Kingdom / Wales / Betws-y-Coed | 2 |
| Craig Peniel | United Kingdom / Wales / Blaenau Ffestiniog | 1 |
| Pared Blanca, El Trebol | Argentina / Río Negro Province / Bariloche Department | 1 |
| Tintagel Head | United Kingdom / England / Tintagel | 1 |