Snowdonia, or (), is a mountainous region and national park in North Wales. It contains all 15 mountains in Wales over 3000 feet high, including the country's highest, Snowdon (), which is tall. These peaks are all part of the Snowdon, Glyderau, and Carneddau ranges in the north of the region. The lower Moelwynion and Moel Hebog ranges lie immediately to the south.
The national park has an area of , and covers most of central and southern Gwynedd and the western part of Conwy County Borough. This is much larger than the area traditionally considered Snowdonia, and in addition to the five ranges above includes the Rhinogydd, Cadair Idris, and Aran ranges and the Dyfi Hills. It also includes most of the coast between Porthmadog and Aberdyfi. The park was the first of the three national parks of Wales to be designated, in October 1951, and the third in the UK after the Peak District and Lake District, which were established in April and May 1951, respectively. The park received 3.89 million visitors in 2015.
Toponymy The name "Snowdon" means "snow hill" and is derived from the Old English elements "snāw" and "dūn", the latter meaning "hill". It is first recorded as Snawdune in 1095. "Snowdonia" is derived from the name of the mountain and is first recorded in 1284, but there is no evidence it survived in common use until it was re-popularised in the 19th century. The Welsh name of the mountain is , and is unrelated to the name of the area.
is first recorded in 1191. It likely derived from , meaning "ridge", with the collective form referring to the area around Snowdon. A popular interpretation is that the name means "place of the eagle", as also means "eagle" and the two meanings are probably cognate.Celtic Culture, 2006, ed. by John T. Koch, p. 719 (Liverpool, 1945), p. 18. Compare the late professor's article in Bulletin of the Board of Celtic Studies, vol. iv, pp. 137–41. The plural of Welsh ('eagle') is or , with no example of a form being attested. A second word , plural , means 'shingles' in modern Welsh; in the old Welsh place name this suggests uneven or upraised ground, a land of hills; 'the uplands' or 'highlands'
Extent Before the designation of the national park in 1951, "Snowdonia" was generally used to refer to a smaller upland area of northern centred on the Snowdon massif. F. J. North, writing in 1949, states that "When the Committee delineated provisional boundaries [of the national park], they included areas some distance beyond Snowdonia proper".
In George Borrow's 1862 Wild Wales, he states that "Snowdon or Eryri is no single hill, but a mountainous region, the loftiest part of which [is] called Y Wyddfa", making a distinction between the summit of the mountain and the surrounding massif. The 1925 Mountains of Snowdonia by H. Carr & G. Lister defines "Eryri" as "composed of the two cantrefs of Arfon and Arllechwedd, and the two commotes of Nant Conwy and Eifionydd",'The Mountains of Snowdonia', pub. by Crosby, Lockwood & Son, London (1925) p. 5. which corresponds to Caernarfonshire with the exception of the Creuddyn Peninsula and the south-west of the Llŷn Peninsula.
A 1941 article by Thomas Cotterill Warrington in the Geographical Association's Geography journal described "Snowdonia" as a "tourist's or mountaineer's term" and defined it as:
In the same article, "Eryri" is defined as the above area and the highlands between Bwlch Mawr and Yr Eifl, with reference to the definition given in The Mountains of Snowdonia.
In the 1946 book National Parks for Britain, Henry Chessell defines Snowdonia is the "mountain district of Carnarvonshire", including the Snowdon, Carneddau, Glyderau, Moel Hebog, and Moelwynion massifs. The area of Merionethshire to the south, bounded by the "glen" between Dolgellau and Trawsfynydd to the east and the Afon Mawddach to the south and including Cadair Idris, is described as "really a southern continuation of Snowdonia".
National park
Eryri National Park (), legally and previously officially named Snowdonia National Park in English, was established in October 1951 under the National Parks and Access to the Countryside Act 1949. The 1947 Hobhouse Report, the precursor to the Act, recommended the creation of a "North Wales National Park" with boundaries similar to those ultimately adopted, but including the area around Lake Vyrnwy and excluding the entire coastal strip from Harlech to Barmouth. It was the third national park to be established in the United Kingdom, following the Peak District and Lake District in April and May 1951.
The park has an area , covering much of central and southern Gwynedd and the western part of Conwy County Borough, and has of coastline. The Hobhouse Report recommended against including the town of Blaenau Ffestiniog in the national park owing to the "disfigurement" caused by its slate quarries, and it forms an enclave near the centre of the area. The coastal towns of Tywyn and Barmouth are also excluded.
The park is governed by a national park authority, which was established in 1995 and has 18 members: 9 appointed by Gwynedd Council, 3 by Conwy County Borough Council, and 6 by the Welsh Government to represent the national interest. The authority's main offices are at Penrhyndeudraeth. Unlike national parks in other countries, national parks in the United Kingdom consist of both public and private land under a central planning authority. More than 26,000 people live within the park, of whom 58.6% could speak Welsh in 2011. While most of the land is either open or mountainous, there is a significant amount of agricultural activity within the park.
The national park authority used the name "Snowdonia" in English-language contexts until November 2022, when it announced that it would begin a transition to using only "Eryri" in order to prioritise the Welsh language name for the area; it also began using in preference to "Snowdon" to refer to the mountain. Following a two-year transition period, the authority announced in November 2024 that the changes would be kept due to its success in gaining support and its adoption by many businesses and by the media. The authority also announced that the national park logo would be changed to remove "Snowdonia".
Geology
The geology of Snowdonia is key to the area's character. Glaciation during a succession of ice ages has carved a distinctive rocky landscape from a heavily faulted and folded succession of sedimentary and igneous rocks. The last ice age ended only just over 11,500 years ago, leaving features attractive to visitors, which have also played a part in the development of geological science and continue to provide a focus for educational visits. Visiting Cwm Idwal in 1841, Charles Darwin realised that the landscape was the product of glaciation. The bedrock dates largely from the Cambrian and Ordovician periods with intrusions of Ordovician and Silurian age associated with the Caledonian Orogeny. There are smaller areas of Silurian age sedimentary rocks in the south and northeast and of Cenozoic era strata on the Cardigan Bay coast, though the latter are concealed by more recent deposits. Low grade metamorphism of Cambrian and Ordovician mudstones has resulted in the slates, the extraction of which once formed the mainstay of the area's economy.
Climate
Snowdonia is one of the wettest parts of the United Kingdom; Crib Goch in Snowdonia is the wettest spot in the United Kingdom, with an average rainfall of a year over the 30-year period prior to the mid-2000s. (There is a rainfall gauge at on the slopes below Crib Goch.)
Geography Mountains The principal ranges of the traditional Snowdonia are the Snowdon massif itself, the Glyderau, the Carneddau, the Moelwynion and the Moel Hebog range. All of Wales' 3000ft mountains are to be found within the first three of these massifs and are most popular with visitors. To their south within the wider national park are the Rhinogydd and the Cadair Idris and Aran Fawddwy ranges. Besides these well-defined areas are a number of mountains which are less readily grouped, though various guidebook writers have assigned them into groups such as the "Arenigs", the "Tarrens" and the "Dyfi hills".
Snowdon's summit at is the highest in Wales and the highest in Britain south of the Scottish Highlands. At , is the highest in Wales outside of northern Snowdonia; , at , is next in line.
Rivers and lakes Rivers draining the area directly into Cardigan Bay are typically short and steep. From north to south they include: the and , which share a common estuary, the and its tributaries the Wnion and the , the smaller and on the park's southern margin the .
A series of rivers drain to the north coast. Largest of these is the Conwy on the park's eastern margin, which along with the drains into Conwy Bay. Further west the and empty into the western end of the Menai Strait. Part of the east of the national park is within the upper Dee (Dyfrydwy) catchment and includes Llyn Tegid (Bala Lake), the largest natural water body in Wales.
A fuller list of the rivers and tributaries within the area is found at List of rivers of Wales.There are few natural bodies of water of any size in Wales; Snowdonia is home to most. Besides Llyn Tegid, a few lakes occupy glacial troughs, including and at and south of . , and to the south and west of Snowdon feature in this category, as do and on the margins of the . There are numerous small lakes occupying glacial cirques, owing to the intensity of past glacial action in Snowdonia. Known generically as tarns, examples are and on Snowdon, within the and on .
There are two large wholly man-made bodies of water in the area, and , whilst a number of the natural lakes have had their levels artificially raised. reservoir and Power Station's are two cases where natural tarns have been dammed as part of pumped storage hydro-electric schemes.
A fuller list of the lakes within the area is found at List of lakes of Wales. In 2023, the park standardised its Welsh language lake names, to be also used in English.
Coast The national park meets the Irish Sea coast within Cardigan Bay between the Dovey estuary in the south and the estuary. The larger part of that frontage is characterised by dune systems, the largest of which are and . These two locations have two of the largest sand/shingle spits in Wales. The and estuaries form the largest indentations, and have large expanses of intertidal sands and coastal marsh which are especially important for wildlife: see #Natural history. The northern tip of the national park extends to the north coast of Wales at Point, west of , where precipitous cliffs have led to the road and railway tunnels.
Settlements
There are only three towns within the park boundary, though there are several more immediately beyond it. is the most populous followed by Bala on the eastern boundary and then Harlech overlooking Tremadog Bay. More populous than these is the town of Blaenau Ffestiniog, which is within an exclave, that is to say it is surrounded by the national park but excluded from it, whilst the towns of Tywyn and Barmouth on the Cardigan Bay coast are within coastal exclaves. in the east, Machynlleth in the south and Porthmadog and Penrhyndeudraeth in the west are immediately beyond the boundary but still identified with the park; indeed the last of these hosts the headquarters of the Snowdonia National Park Authority. Similarly the local economies of the towns of Conwy, Bethesda, and Llanberis in the north are inseparably linked to the national park as they provide multiple visitor services. The lower terminus of the Snowdon Mountain Railway is at Llanberis. Though adjacent to it, and are less obviously linked to the park.