"Loch Ness is the second-largest Scottish loch by surface area after Loch Lomond at 56.4 km² (21.8 sq mi), but due to its great depth is the largest by volume.
It contains more fresh water than all lakes in England and Wales combined. Its deepest point is 230 m (754 feet) <1>, deeper than the height of London's BT Tower at 189 m (620 feet).
Loch Ness is the largest body of water on the Great Glen geologic fault, which runs from Inverness in the north to
Fort William in the south. The Caledonian Canal, which links the sea at either end of the fault, uses Loch Ness for part of its route."
http://en.wikipedia.org/wiki/Loch_Ness"Where Urquhart Castle overlooks Loch Ness.
It was in its day one of the largest strongholds of medieval Scotland, and remains an impressive structure, splendidly situated on a headland overlooking Loch Ness."...that is, if you beleive in the "First Laddie."http://en.wikipedia.org/wiki/Urquhart_Castle