Llangynog (grid reference SJ053261) lies at the confluence of the Afon Eirth and the Afon Tanat at the foot of the Berwyn range in Powys, Wales. Pop c.300
It lies at the foot of the Milltir Cerrig mountain pass on the B4391 road, which runs between Llan Ffestiniog and Llanfyllin (though the B4391 road number 'disappears' between the western end of Llyn Celyn and Bala).
It is surrounded by mountains and is a popular base for walkers. It boasts two pubs and a free car park with free toilet facilities as well as numerous holiday cottages and chalets for let. It is out of range from all mobile telephone services but has a public phone box although this is known to be temperamental and is consistently out of order. Landline phones are readily available for free from both local pubs.
It was the western terminus of the Tanat Valley Light Railway (Llynclys - Llangynog) 15 miles: opened January 5, 1904; closed (passenger traffic) 1951.
It is close to the pilgrimage shrine of Saint Melangell at the church of Pennant Melangell (grid reference SJ024265).
Llangynog also has a local crown green bowling club, who are currently playing in the Oswestry League.