Category: Park/Wilderness/Nature
City: Yellowstone National Park
Isa Lake is one of the world's most unusual lakes because its water drains to both the Atlantic and Pacific oceans – and does it backwards. The waters flowing west from the lake eventually reach the Atlantic, through the Firehole, Madison, Missouri and Mississippi rivers to the Gulf of Mexico. The water which leaves the east end of the lake flows to the Pacific by way of the Lewis, Snake and Columbia rivers.