The Pen y Waun nature reserve consists of two small fields situated on the edge of Waun-y-Mynach common. The fields were former garden plots for nearby cottages.
This wildflower meadow has always been managed traditionally with grazing by cattle or ponies from spring to autumn. This kind of rough, damp grassland is known in Wales as Rhos pasture and is becoming rare. Please keep dogs on a lead as skylarks often nest within the rough grass.