The spectacular Aberglaslyn Pass is a narrow gorge south of Beddgelert within the Snowdonia National Park. Intersected by the Afon Glaslyn (Glaslyn River) on its journey from Mount Snowdon to the Bay of Cardigan, the Aberglaslyn Pass is best appreciated whilst traversing the footpaths running alongside the river.
Before building the Cob at Porthmadog in the early 19th century, the tide reached up to Aberglaslyn Bridge, and the gap provided important access to the north coast, avoiding sailing around the Llŷn Peninsula.
Just below the bridge, lies Llyn Glas, the former site of a harbour used to transport copper ore from Cwm Bychan. The copper sulphate of the surrounding hills imbues the Afon Glaslyn with its distinctive turquoise tinge. The spray from the river and the coolness of the gorge provides an ideal environment for ferns, mosses and liverworts, with the river itself home to Otters, Salmon, Kingfishers and Dippers.
Over the bridge and high above the gorge, stands Coedydd Beddgelert and Aberglaslyn George. This expanse includes a 1.5km stretch of the Afon Glaslyn and varied types of native woodland primarily located along the steep valley sides dominated by boulders and rocky crags. The canopy is characterised by Sessile Oak, Birch and Beech trees, with some scattered Rowan, Holly, Ash and Sycamore. The woodland in this moist and largely shaded site supports a rich diversity of mosses, liverworts and lichens in addition to a colony of Lesser Horseshoe Bats, known to hibernate within the disused mines nearby.
There is a wealth of folklore relating to the area, including stories about a supernatural black dog that could be seen in the area, and the "white lady", a rock on the eastern side of the gap.
A popular starting point for most walks around this area begins at the National Trust Car Park, situated in Nantmor village.