Maen Llia

Maen Llia is a standing stone which sits on moorland at grid reference SN924192 in the Brecon Beacons National Park in Powys, Wales.

It is a popular tourist attraction, lying just 60 yards off a minor road running north from the village of Ystradfellte in the Waterfall Country towards the hamlet of Heol Senni and Brecon, the county town of Brecknockshire.

This pattern contains some unique geometry not known to exist anywhere else in the world, although some aspects of it can be discerned at Stonehenge.

Another significant standing stone, Maen Madoc, lies just off the old Roman road known as Sarn Helen about 2 miles (3.5 km) to the south.

This tale seems likely to be an allusion to the fact that its shadow is cast across the moorland as far as the river when the sun is low in the evening sky.