Swnt Enlli (the Bardsey Sound) is approximately two miles wide and separates Ynys Enlli (Enlli) from the western tip of Ll?n. This is one of the most treacherous stretches of water around the UK, with the tide running at up to 10 knots - Ynys Enlli means "island of the tides".

Enlli is about two miles long by half a mile wide (at it's widest point!). It has a "mountain" (Mynydd Enlli), lighthouse, beach and small harbour where the boats that bring visitors to the island can moor at high tide. There are a handful of houses and outbuildings centred around what is left of the ancient monastery (stone from the monastery was used to help build some of the houses). A more recent chapel lies nearby at the foot of Mynydd Enlli. There is a small shop and basic toilet facilities in the centre of this "village".

There is no better place to get away from modern life - Enlli has no electricity, and water is gathered from springs on the hillside. However this is part of what attracts visitors here, as the island has for hundreds of years. Pilgrims have travelled to Enlli for centuries, and at one time, three journeys to the island equalled one to Rome. The island is said to be the burial place of 20,000 saints. Enlli is important for wildlife, especially birds and there is an observatory on the island.

The Ymddiriedolaeth Ynys Enlli (Bardsey Island Trust) bought the island in 1979 and now manages it by stationing a couple of households on the island on a permanent basis. The Trust's office is located within Plas Glyn-y-Weddw in Llanbedrog. Trips to the island run mainly from Porth Meudwy near Aberdaron.