Loch Ness is a large, deep, freshwater loch in the Scottish Highlands.
The Scooby-Doo Show
Mystery Inc. headed to Scotland to help Velma's friend Aggie McDuff, whose ancestral castle home (which she's turned into a tourist attraction) was being haunted by the ghost of her great-grandfather Finnyan McDuff, who in turn had summoned the Loch Ness Monster to help him scare away potential tourists. (A Highland Fling with a Monstrous Thing)
Scooby-Doo! and the Loch Ness Monster
Fred, Daphne, Velma, and Shannon traveled to the Loch Ness in Fiona Penbrooke's boat while Shaggy and Scooby-Doo checked around the area of Blake Castle; the duo got lost in a fog bank and ended up in on the boat.