Lake Gravity Falls

Lake Gravity Falls is a lake in Gravity Falls. It first appeared in "The Legend of the Gobblewonker". The lake appears to be surrounded by cliffs on three sides, with a beach on the one side without a cliff. It is a lake where a lot of citizens go to do their fishing. Many of the local fisherman don't trust Grunkle Stan. Lazy Susan fishes here.

Overview
Lake Gravity Falls is a large body of water near the town of the same name. It is often used for fishing, with nearly the whole town turning out on opening day of fishing season. It has at least one waterfall running into it, which houses a secret cave behind it. The cave seems to have been written about in 3. A monster known as the Gobblewonker is said to live in the lake.

The lake also houses a small island that is known as Scuttlebutt Island, a mysterious and foreboding area where the Gobblewonker is known to frequent. The island also is home to a colony of beavers.

History
The lake is first seen in "The Legend of the Gobblewonker", when fishing season begins. It is there that Dipper and Mabel go looking for the Gobblewonker on Scuttlebutt Island. After they find the monster, it chases them through the lake, until the escape into the cave behind the lake's waterfall. After discovering that the Gobblewonker was, in actuality, a machine created by Old Man McGucket, Dipper, Mabel, and Soos have an evening of fishing with Grunkle Stan. At the episode's end, a beast that appears to be the true Gobblewonker is shown swallowing one of Dipper's cameras while underwater, showing that the creature does actually exist, and makes its home in the lake.

It also appears as the first three levels in Mystery Tour Ride, where you can see the giant gnome monster and The Gobblewonker.