| Tyrrau Mawr\Craig-las | |
| Elevation M: | 661 |
| Prominence M: | 103 |
| Parent Peak: | Cadair Idris |
| Listing: | Hewitt, Nuttall, HuMP |
| Language: | Welsh |
| Location: | Gwynedd, Wales |
| Range: | Cadair Idris |
| Grid Ref Uk: | SH711130 |
| Topo: | OS Landranger 124, Explorer OL23 |
| Easiest Route: | Hike |
Tyrrau Mawr or Craig-las is a subsidiary summit of Cadair Idris in the Snowdonia National Park, in Gwynedd, northwest Wales. It lies to the west of Cyfrwy, and can be climbed by taking a west bearing from the Pony Path at Rhiw Gwredydd. Its north face is a crag, known as Craig-las. Below the crags lies Llyn Cregennen with its small island. The reflection of Craig-las from this lake is one of the famous images associated with Snowdonia.
The summit is grassy and marked by a few stones. To the east of the summit lies the large ancient cairn, Carnedd Lwyd. It is often climbed in combination with Craig-y-llyn.[1]