Norris Geyser Basin – Yellowstone’s Hottest, Oldest, Tallest
Norris is one of the most extreme environments on the face of the Earth.
Boiling waters; a rainbow of colors; geysers galore; and a personality more fickle than any teenager: The Norris Geyser Basin is a geological area forever wrought in turmoil.
And that’s why it’s so darn cool!
Geyser basins are characterized by the presence of, you guessed it, geysers. These geothermal hotspots (literally) are referred to as basins because they are nearly always lower than the surrounding terrain due to erosion, faults, and the underlying hot water.

Norris ranks as Yellowstone National Park’s hottest and most changeable thermal area, making it one of the most extreme environments on the face of the Earth. Most of its thermal features have temperatures above the boiling point, which is 199°F due to the area’s elevation. It also claims the record for the highest temperature ever recorded in any of Yellowstone’s geothermal areas. There, a scientific-drill hole just 1,087 feet below the surface measured temperatures at a roiling 459°F.
But it’s not just the temperatures that make Norris so notable. The colors too impress thanks to a combination of minerals and life forms. The area tends to have more milky blue features than other geothermal spots because of a high silica concentration dissolved in the hot water. Reddish orange is another prominent hue thanks to the (poisonous!) iron oxides and arsenic compounds. Cyanobacteria contribute to the more orange-colored areas. Other parts of Norris, those with natural springs, tend to be emerald green due to the blue of refracted light in combination with the yellow of sulfur lining the pool.

The best way to get a great vantage point of these features is to hit one of the boardwalks circling through the area. But don’t step off the boardwalk. Places like Norris are constantly changing and feature hollow areas that may have only a thin layer of rock over them. Beneath that layer of rock: boiling, bacteria-filled water. Although most burns received in thermal areas are second and third degree, people have died from falling into thermal features.

The Norris Geyser Basin Consists of Three Areas
Porcelain Basin – a .75 mile dirt trail and boardwalk cascades around a milky colored, steaming landscape barren of trees.
Back Basin – a 1.5 mile trail of boardwalk and dirt trail encircles a heavily wooded area of many geysers and hot springs.
One Hundred Springs Plain – an off-trail section of the Norris Geyser Basin that is very acidic, hollow, and dangerous. Travel is discouraged without the guidance of knowledgeable staff members.