Yellowstone National Park
Yellowstone National Park has one of the world's largest petrified forests, trees which were long ago buried by ash and soil and transformed from wood to mineral materials. This ash and other volcanic debris are believed to have come from the park area itself as the central part of Yellowstone is the massive caldera of a supervolcano. The park contains 290 waterfalls of at least , the highest being the Lower Falls of the Yellowstone River at .
Jackson Lake
Jackson Lake is in Grand Teton National Park in northwestern Wyoming. This natural lake was enlarged by the construction of the Jackson Lake Dam, which was originally built in 1911, enlarged in 1916 and rebuilt by 1989. The top of the lake is utilized by farmers in Idaho for irrigation purposes. The lake is the remnant of large glacial gouging from the neighboring Teton Range to the west and the Yellowstone Plateau to the north. The lake is primarily fed by the Snake River, which flows in from the north, and empties at Jackson Lake Dam. Jackson Lake is one of the largest high altitude lakes in the United States, at an elevation of above sea level. The lake is up to long, wide and deep. The water of the lake averages below , even during the summer.