A freshwater Scottish loch on the Highland Boundary Fault, Loch Lomond is the largest loch in all of Great Britain as measured by surface area. Lomond is known for containing many islands, including Inchmurrin, the largest freshwater island in the British Isles. A popular leisure destination, Lomond is featured in song and other forms of pop culture.

Loch Lomond measured 24 miles long and varies between 0.75 miles and 5 miles wide depending on where along the stretch you measure. The average depth of the loch is 121 feet, with a maximum depth of just over 600 feet. The surface area, by which this loch is considered the largest in the region, measures 27 square miles. While it may be the largest by surface area, because of its shallowness in some areas, the loch is second-largest by volume, falling behind Loch Ness.

Loch Lomond contains thirty or more other islands depending on the water level. Several of them are large by the standards of British bodies of freshwater. "What a large part of Loch Lomond's beauty is due to its islands, those beautiful green tangled islands, that lie like jewels upon its surface," wrote English travel writer, H.V. Morton.

The loch is one of the premier boating and watersports destinations in all of Scotland. Tourism brings in a large amount of money for the region, with venues catering to those looking to kayak, canoe, windsurf, jetski, speedboat, and more. So popular is the area that the Loch Lomond Rescue Boat patrols the loch 24 hours a day.