Hang around Lake Champlain long enough and you are bound to hear about Champ. Like the Loch Ness in Scotland, the lake is supposed to be the abode of a modern-day sea monster that has been “sighted” many times over the past 400 years. In fact, Samuel de Champlain himself supposedly spotted a “20 foot serpent thick as a barrel and [with] a head like a horse” when he discovered the lake in 1609. In 1873, circus impresario P. T. Barnum offered $50,000 as a reward for its skin; subsequently both Vermont and New York have passed laws against harming the (supposed) creature.

The most conclusive evidence of the monster is a photo taken in 1977 by vacationer Sandra Mansi that clearly shows a curved neck and head poking out of the lake. When Champ fans try to explain what the “monster” is, however, they begin running into problems. Most theories hold that the creature is related to a dinosaur called a plesiosaur that got trapped in the lake when it used to be an arm of the ocean.

However, the lake is only 10,000 years old, while plesiosaurs are thought to have been extinct for 65 million years. So in order to have a dinosaur in the lake, you’d need to have one plesiosaur who had been alive 65 million years — or to have a viable current breeding population, you’d need 500 plesiosaurs in the lake today.

Whatever the truth, Champ has been embraced as a symbol by locals who have put his moniker on everything from Champ’s Potato Chips to Burlington’s Lake Monsters, a minor-league baseball team.