Best time to travel to Yellowstone National Park

Isa Lake in Yellowstone National Park

Located at a high elevation, Isa Lake flows to west and east and makes its path to the Atlantic and Pacific Oceans. And this happens only at a certain time of the year

Best time: March–May

Isa Lake
Isa Lake

Isa Lake is a narrow basin located at the summit of the Craig Pass, at the height of 2,518 metres. You can find it between the Old Faithful and West Thumb geyser basins on the Yellowstone National Park's Grand Loop Road. It was named after a Miss Isabel Jelke, of Cincinnati.

This lake is one of most unique lakes in the world because it is the only natural basin that drains into both the Atlantic and the Pacific Oceans. This unique phenomenon occurs every spring, when the snow from the mountains melts, overflowing the lake with water, which goes in two directions.

The western end of the lake flows into the Firehole River, to the Missouri and Mississippi Rivers and then to the Gulf of Mexico. The eastern end runs into Shoshone Lake, which drains into the Lewis, Snake, and Columbia Rivers and heads to the Pacific Ocean.

Practical info

When does the unique phenomenon of Isa Lake draining into the Atlantic and Pacific Oceans occur?

Isa Lake's unique phenomenon of draining into the Pacific and Atlantic Oceans occurs only once a year during the spring season. This phenomenon happens when snow melts from the mountains, causing the lake to overflow with water. Being the only natural basin to drain into both the Pacific and Atlantic Oceans, the western side of the lake flows into the Firehole River, Missouri, Mississippi, and eventually the Gulf of Mexico, and the eastern end flows into the Lewis, Snake, and Columbia Rivers, which leads to the Pacific Ocean. Show more

What is the location of Isa Lake in Yellowstone National Park?

Located at an elevation of 2,518 metres, Isa Lake is situated between the Old Faithful and West Thumb Geyser Basins along the Grand Loop Road. The narrow basin is located at the summit of Craig Pass and distinguished by its high elevation relative to its surroundings. Visitors may easily locate it via the park map or from the help of park rangers. A scenic drive to the lake through the park can be an option for visitors to consider. Show more

At what altitude is Isa Lake located?

At a height of 2,518 metres above sea level lies Isa Lake, a unique feature within Yellowstone National Park. The lake is the highest feature in the region and is located at the summit of Craig Pass, linking the Old Faithful and West Thumb Geyser Basins. Visitors may want to take extra precautions while hiking in the region due to the high elevation, such as carrying extra oxygen or taking breaks regularly. Show more

What is the recommended way of reaching Isa Lake?

Reaching Isa Lake can be achieved easily by taking the Grand Loop Road through Craig Pass, a popular stop-off point for visitors traveling between the Old Faithful and West Thumb Geyser Basins. Running parallel to the lake is the road, with a nearby parking lot that visitors may use. It is a short walk from the parking lot to the lake, or visitors may ask park rangers for the direction to the lake if needed Show more

Are there any additional activities for visitors to do around Isa Lake besides observing the water flow?

Isa Lake's high elevation makes it a perfect location for visitors wanting to explore the natural beauty of Yellowstone National Park, such as hiking and wildlife spotting. Visitors may experience the nearby trails and natural features such as Mount Washburn Trail and Fountain Paint Pot Trail. Further, visitors may want to explore the other lakes near Isa Lake, such as Shoshone Lake, to relax and appreciate the outdoors. Show more

Ask a question

Find hotels and airbnbs near Isa Lake (Map)

Last updated: by Eleonora Provozin