| Senni Beds | |
|---|---|
| Stratigraphic range: Devonian | |
 Mynydd Troed, the upper part of the hill consisting of the Senni Beds Formation | |
| Type | Formation |
| Unit of | Old Red Sandstone |
| Lithology | |
| Primary | Mudstone |
| Other | Sandstone |
| Location | |
| Region | Wales |
| Country |  United Kingdom |
The Senni Beds is the former name of the Senni Formation in Wales. It preserves fossils dating back to the Devonian period.
