Craig yr Aderyn

Craig yr Aderyn is a rocky summit in Gwynedd, Wales, rising prominently from the Dysynni Valley with steep cliffs and exposed rock formations. The two distinct peaks create a striking landscape feature with clearly visible geological structures throughout the site.

The summit contains remains of an Iron Age fortification built in two distinct phases. This shows the site served defensive purposes over an extended period and was rebuilt or modified at different times.

Local Welsh speakers call the two main peaks Y Palis Mawr and Y Palis Bach, referring to a large and small fortification. These names show how communities understood and shaped their relationship with this distinctive landform.

The site is protected from April through July to safeguard nesting birds, so access is limited during this season. Visitors should check current access guidelines beforehand and bring suitable footwear for rocky and steep terrain.

This location holds Wales's largest inland cormorant colony, established unusually far from the sea at about five miles from shore. This settlement away from typical coastal habitats shows a remarkable adaptation of seabirds to an unexpected environment.