Loch Lomond  is a freshwater Scottish loch. It is the largest inland stretch of water in Great Britain by surface area. The loch contains many islands, including Inchmurrin, the largest fresh-water island in the British Isles. Loch Lomond is a popular leisure destination and is featured in song The Bonnie Banks o' Loch Lomond.
|Location||West Dunbartonshire/Argyll and Bute/Stirling|
|Primary inflows||Endrick Water, Fruin Water, River Falloch|
|Primary outflows||River Leven|
|Catchment area||696 km2 (269 sq mi)|
|Max. length||39 km (24 mi)|
|Max. width||8 km (5.0 mi)|
|Surface area||71 km2 (27 sq mi)|
|Average depth||37 m (121 ft)|
|Max. depth||190 m (620 ft)|
|Water volume||2.6 km3 (0.62 cu mi)|
|Residence time||1.9 years|
|Surface elevation||7.6 m (25 ft)|
|Islands||60 (Inchcailloch, Inchmurrin, Inchfad)|
|Sections/sub-basins||north basin, south basin|
Loch Lomond lies on the Highland Boundary Fault, the boundary between the Lowlands of Central Scotland and the Highlands. It is 24 miles (39 kilometres) long and between 0.75 mile (1.21 km) and 5 miles (8 km) wide. It has an average depth of about 121 feet (37 metres), and a maximum depth of about 620 feet (190 metres). Its surface area is 27 square miles (71 km2), and it has a volume of 0.62 cubic miles (2.6 km3).
Of all lochs and lakes in Great Britain, it is the largest by surface area, and the second largest (after Loch Ness) by water volume. Within the United Kingdom, it is surpassed only by Lough Neagh and Lower Lough Erne in Northern Ireland. In the British Isles as a whole there are several larger loughs in the Republic of Ireland.
- Scottish Gaelic: Loch Laomainn
- Peter Matthews, ed. (1994). The Guinness Book of Records 1995. Guinness World Records Limited. p. 17. ISBN 0-85112-736-3.
- Worsley, Harry (1988). Loch Lomond: the loch, the lairds and the legends. Glasgow: Lindsay. ISBN 978-1-898169-34-5.
- "Scotland’s Water Environment Review 2000-2006" SEPA. Retrieved 11 October 2008.
- Whitaker's Almanack 1991. London: Whitaker, 127.