Isa Lake
Isa Lake is located in Yellowstone National Park, in the U.S. state of Wyoming. The lake straddles the continental divide at Craig Pass and was first discovered in 1891 by Hiram M. Chittenden, who was exploring the best routes for a road to connect Old Faithful and West Thumb geyser basins. Chittenden named the lake after Miss Isabel Jelke, from Cincinnati, though it is not clear why.
Isa Lake is believed to be one of the few natural lakes in the world which drain to two different oceans, another being Wollaston Lake. The east side of the lake drains by way of the Lewis River to the Pacific Ocean and the west side of the lake drains by way of the Firehole River to the Gulf of Mexico.
The lake is easy to visit as it is adjacent to the road that now connects the Old Faithful and West Thumb geysers basins, on what is known as the "lower loop" of the figure-eight roadway which traverses through Yellowstone. The great yellow pond-lily thrives in the lake.
