Penmaenmawr is a town and community in Conwy County Borough, Wales, which was formerly in the parish of Dwygyfylchi. It lies on the North Wales coast between Conwy and Llanfairfechan and was an important quarrying town, though this industry is no longer a major employer. The population of the community was 4,353 in 2011, including Dwygyfylchi and Capelulo.
It was named after Penmaenmawr mountain, which stands above the sea immediately west of the town. Much of its formerly rounded top (with an old hill-fort) has been quarried away, leaving the present-day lower flat top.
The town was bypassed by the A55 Expressway in the 1980s, losing its old Edwardian period promenade in the process, which was largely replaced by a modern one. Penmaenmawr is noted for its spectacular mountain and coastal walks. Nearby are the popular attractions of Bwlch Sychnant ( Sychnant Pass) and Mynydd y Dref, and the town also lies partly within Eryri, the Snowdonia National Park.