From Wikipedia, the free encyclopedia

West Thumb may refer to the following features in Yellowstone National Park:

  • The most western portion of Yellowstone Lake formed by a volcanic eruption 174,000 years ago
  • West Thumb Geyser Basin, a thermal area on the shores of that portion of Yellowstone Lake
  • West Thumb Junction, used to refer to the general area of the park, often used interchangeably with nearby Grant Village