The Snake River begins its thousand mile journey to the Columbia River in Yellowstone National Park, Wyoming. Volcanic activity dating back about 17 million years ago created the canyon. About 15,000 years ago a natural dam on Lake Bonneville, a glacial lake larger in size than today's Lake Michigan, failed releasing a torrent of water that reshaped the entire canyon. The Canyon River Trail, a 12-mile hiking trail between Swan Falls Dam and Celebration Park follows the Snake River.