Facts and figures
Key statistics, records, and historical firsts about Yr Wyddfa (Snowdon) — from the geology that formed it 450 million years ago to the records set by the mountain railway that has run to its summit since 1897.
Summit and geography
Summit facts
- Height
- 1,085 m(3,560 ft)
- Prominence
- 1,039 m
- OS grid reference
- SH 60986 54375
- Coordinates
- 53.0685°N4.0763°W
- Summit building
- Hafod Eryri
- Build cost
- £8.4m
- National Park
- Eryri
- NNR area
- 1,671 ha
Highest point in Wales and England
Third highest prominence in the British Isles
Ordnance Survey
Opened 12 June 2009 — highest building in the UK
At 2009 prices. Ray Hole Architects
Designated 1951 as Snowdonia NP; renamed Eryri 2022
Snowdon National Nature Reserve
The Mountain Railway
Railway facts
- Opened (public service)
- 1897
- Route length
- 7.5 kmone way
- Gauge
- 800 mm
- Maximum gradient
- 1 in 5.5
- Type
- UK's only public rack railway
- Hybrid locos
- 2020
- Steam locos
- 1895–1923
- Journey time
- ~1 hrascendingverify
Opening day 1896 ended in derailment; public service from June 1897
Narrow gauge; Abt rack-and-pinion system
18.2% — handled by the rack system throughout
The only public rack-and-pinion railway in the United Kingdom
World's first rack-and-pinion diesel-battery hybrid locomotives
Original Swiss-built locos still in operational heritage service
Visitor numbers and infrastructure
Visitor facts
- Annual walkers
- 600,000+verify
- MRT callouts (2025)
- ~358verify
- MRT founded
- 1964
- Main approach
- Llanberis Path
- Summit post box
- Yes
- 24hr defibrillator
- Summit
- Paths maintained
- 6 main + links
- Welsh language
- Yr Wyddfa
One of the UK's busiest mountain rescue teams
Most walked route; serves the Mountain Railway station
Letters receive a summit frank
Outside Hafod Eryri, insulated cabinet, accessible year-round
Snowdon Upland Path Partnership maintains major routes
Primary name since November 2022 by Eryri NPA resolution
Weather and environment
Weather and environment
- Days in cloud
- 200+/year
- Annual rainfall
- 300+ cm
- Summit/valley temp diff
- 8–10°C
- Wind record
- >100 mph
- Freezing level (winter)
- 0 m+
- Dark Sky Reserve
- Dec 2015
~70% of the time at summit level
Approximately five times London's average
Standard atmospheric lapse rate on a typical day
Recorded at summit in severe storm conditions
The entire mountain can be below freezing in cold spells
Eryri International Dark Sky Reserve — one of ~18 worldwide
Geology and landscape
Geology and landscape
- Rock age
- ~450 Ma
- Rock types
- Rhyolite, tuff, basalt
- Glaciation peak
- ~20,000 years ago
- Llyn Llydaw
- 45 ha / 58 m deep
- Glaslyn
- 7.3 ha / 39 m deep
- UNESCO listing
- 2021
Ordovician period — submarine volcanic origin
Snowdon Volcanic Group — pyroclastic and lava flows
Devensian glaciation — carved the cwms and arêtes
Largest mountain lake on the Snowdon massif
Blue-green from copper — directly below the summit crags
Slate Landscape of Northwest Wales — covers Dinorwic and others
Historical firsts and milestones
First recorded ascent by Welsh botanist Thomas Johnson, who documented alpine plants on the upper slopes.
Name "Snawdune" (Snowdon) first appears in the Anglo-Saxon Chronicle — Old English for snow hill.
Welsh name "Weddua vaur" (Yr Wyddfa) first appears in documented records.
John Morton establishes guiding service from Llyn Cwellyn as the "Snowdon Ranger" — oldest formal guide route.
Prime Minister Gladstone, aged 82, opens the Watkin Path — Britain's first formally designated summit footpath.
Snowdon Mountain Railway opens. On opening day, locomotive No. 1 derails and is destroyed; one passenger dies; the number is never reissued.
Railway reopens with safety modifications. Continuous commercial operation begins.
British Everest expedition (including Hillary) trains on Snowdon's crags. Based at the Pen-y-Gwryd Hotel.
Hafod Eryri opens (12 June), replacing the condemned predecessor. Cost: £8.4m. Architect: Ray Hole.
World's first rack-and-pinion diesel-battery hybrid locomotives enter service on the Snowdon Mountain Railway.
Slate Landscape of Northwest Wales inscribed as UNESCO World Heritage Site.
Eryri National Park Authority formally adopts Yr Wyddfa as the primary name for the mountain.