Ben Nevis (Gaelic: Beinn Nibheis) is the highest mountain in the British Isles. It is located at the western end of the Grampian Mountains in the Lochaber area of Scotland, close to the coastal town of Fort William.

Known simply as "The Ben" to many walkers and climbers, it attracts an estimated 100,000 visitors a year, around three-quarters of whom use the well-constructed Pony Track from Glen Nevis on the south side of the mountain. For climbers and mountaineers the main attraction lies in the 700-metre-high cliffs of the north face: among the highest cliffs in Britain, they harbour some classic scrambles and rock climbs of all difficulties, and are one of the principal locations in the UK for ice climbing.

The summit, at 1,344 metres (4,406 feet) above sea level, features the ruins of an observatory which was permanently staffed between 1883 and 1904. The meteorological data collected during this period is still important for an understanding of Scottish mountain weather. C.T.R. Wilson was inspired to invent the cloud chamber after a period spent working at the observatory.