Grand Prismatic Spring

Grand Prismatic Spring in Yellowstone National Park is the largest hot spring in the United States and the third largest in the world, measuring 90 meters in diameter and up to 50 meters deep. Its vividly colored rings — blue in the center graduating through teal, green, yellow, and orange to a deep red at the edges — are caused by heat-loving bacteria (thermophiles) that form pigmented mats at different temperatures. The spring is best appreciated from an overlook trail that provides the aerial perspective needed to see its full rainbow.

• Categoryattraction
• Opening Hours24/7