Bracken in a woodland clearing at Allt y Benglog National Nature Reserve - geograph

Allt y Benglog is a small national nature reserve near

Dolgellau Dolgellau (; ) is a town and Community (Wales), community in Gwynedd, north-west Wales, lying on the River Wnion, a tributary of the River Mawddach. It was the traditional county town of the Historic counties of Wales, historic county of Merion ...

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

. Its position on the lower slopes of

Rhobell Fawr Rhobell Fawr is the site of an ancient volcano that was active during the Early Ordovician period in the Arenig range within the Snowdonia National Park. Despite its modest height of 734 m (2,408 feet), it is a mountain with views ...

, one of north Wales’ extinct

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

es, results in an unusual mix of plants and trees which spring from its subterranean mix of

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

s. A permanently damp atmosphere is created through a combination of numerous

waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in seve ...

s and good tree coverage, and allows an unusually rich variety of moisture-loving

mosses Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta ('' sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and ho ...

, plants and trees to thrive.

Notes

National nature reserves in Wales Nature reserves in Gwynedd Brithdir and Llanfachreth {{Gwynedd-geo-stub