I like to get out here and explore Yellowstone’s geyser basins when the day is still young. The Midway Geyser Basin is one of my favorites. At Midway you’ll find two of the largest thermal features of their type found anywhere in the world.
Even before you get to the footbridge that crosses the Firehole River, the run-off from Excelsior Geyser draws attention to the volume of energy being release by this basin. Excelsior discharges over 5,800,000 gallons of hot water a day into the river.
During the 1880’s, Excelsior Geyser was one of the most impressive geysers in the world. Some eruptions went as high as 300 feet and they were as wide as they were tall. After over ninety years of inactivity, Excelsior showed signs of awakening in 1985. For 46 hours, eruptions were frequent and at times as high and wide as 80 feet.
Just down the boardwalk from Excelsior is one of the largest and deepest hot springs in the world. Grand Prismatic Spring is 370 feet across and 125 feet deep. As the water cools it creates the perfect environment for the brilliantly colorful bacteria mat that surrounds the pool.
The bright colors are communities of microbes called thermophiles. These communities are fragile. Please stay on walkways and never touch the bacteria.
Watch for the colored steam above Grand Prismatic. The steam reflects the brilliant colors below. Midway Geyser Basin is a treasure at the end of a rainbow.