Snowdonia has an incredible history of volcanic, ice-age and glacial activity dating back from roughly 700 million years ago. It was once even completely under the sea! Snowdon itself at 1058m is in epicentre of a volcano as is the lesser known Rhobell Fawr 756m. Cwm Idwal is a stunning example of glacial erosion with the famous 'Devil's Kitchen'. The mountains, once joined into a continuous chain where the ancient tectonic plates moved and lifted, have been carved and 'quarried' by ice. This, together with ongoing erosion and weathering effects, leaves the magnificent landscapes found within the National Park today. To walk with even a small knowledge of this adds an extra thrill to one's awareness and walking experience.