the Loch Ness Monster aka Nessie
The Loch Ness Monster is a creature or group of creatures said to live in Loch Ness, a deep freshwater loch (lake) near the city of Inverness. Nessie is generally considered a lake monster. Along with Bigfoot and Yeti, Nessie is perhaps the best-known mystery in cryptozoology.Most mainstream scientists and other experts find current evidence supporting Nessie unpersuasive, and regard such reports as hoaxes or misidentification of mundane creatures.
source and more information
No matter if you do or don't actually believe in Nessie, the myth still makes for an intriguing story. I just happen to believe that Nessie does exist, which is probably due to me being Scottish myself :)
Library
The links open in a new window.The Loch Ness Monster: The Evidence
Nessie: The Legend of the Loch Ness Monster
The Complete Visitor's Guide to Loch Ness, Inverness and the Loch Ness Monster
The Encyclopaedia of the Loch Ness Monster