Norris Geyser Basin Trails

NPS / Matt Poyner

Norris is one of the hottest and most acidic of Yellowstone’s hydrothermal areas. It is part of one of the world’s largest active volcanoes. Many hot springs and fumaroles here have temperatures above the boiling point (200ºF / 93ºC).

Water fluctuation and seismic activity often change features. Norris is near the intersection of three major faults. One runs from the north; another runs from the west. These two faults intersect with a ring fracture from the Yellowstone Caldera eruption 640,000 years ago. These conditions helped to create this dynamic geyser basin.

Notes: Thermal activity throughout this entire area. Stay on the boardwalks and designated trails at all times.

Check out the hike details and accessibility information at the bottom of this page.

Details

Duration

30-90 Minutes

There are two main loops: one through the Porcelain Basin and one through the Back Basin. The Porcelain Basin is the shorter of the two.

Activity

Front-Country Hiking

Pets Allowed

No

Activity Fee

No

Entrance fees may apply, see Fees & Passes information.

Location

Norris Geyser Basin

Reservations

No

Season

Spring, Summer, Fall

Norris Geyser Basin is only accessible by snowmobile during the winter months.

Time of Day

Any Time

Accessibility Information

The trails through the geyser basin are a combination of boardwalks, paved paths, and unpaved paths.

The trail leading from the Norris Geyser Basin Museum & Information Station down into both basins is steep and uneven.

Changing & Unpredictable

Each year at Norris new hot springs and geysers appear; others become dormant. Geologic events trigger many of these changes. Even small earthquakes can alter hydrothermal behavior. Some transformations are brief; others last longer. Geysers and hot springs may also change. The chemistry of some of the Norris hot springs dissolves underground rock. In other Norris hot springs, hot water moves toward the surface, depositing dissolved minerals along subterranean passages and around the surface vents. Sometimes, these deposits can choke off the flow of water. New features may be born as hot, pressurized water seeks a new route to the surface.

Clear pools can become muddy and boil violently, and some may temporarily become geysers. Geysers cease erupting or have altered cycles. New features appear. This sudden activity is Norris Geyser Basin known as a “thermal disturbance” and can last a few days, or more than a week. Gradually, most features return to “normal.”

Why this happens is not fully understood. Norris has the greatest water chemistry diversity among Yellowstone’s hydrothermal areas. Multiple underground hot water reservoirs exist here and as their water levels fluctuate, concentrations of chloride, sulfate, iron, and arsenic change. Although Norris is known for its acid features, it also has alkaline hot springs and geysers. As underground water and chemistry shift suddenly, they could contribute to dramatic changes in minerals and pH. Further study will help unravel this mystery.

Thermophile communities change as water cools and chemistry changes at the edges of features and runoff channels.

NPS

The Colors of Norris

Many of the colors you see here are evidence of thermophiles (heat-loving microorganisms) and their activity.

• Yellow deposits here typically contain sulfur. Some thermophiles live in these areas because they use chemicals like sulfur for energy, sometimes creating hydrogen sulfide gas (the rotten egg odor). They form communities of mats and streamers that look like waving clumps of hair, in the hottest acidic runoff, which measure between 140°F/ 60ºC and 181°F / 83ºC.
• Dark brown, rust, and red colors abound in Norris and contain varying amounts of iron. Red-brown mats may also contain bacteria and archaea that help build the mats by metabolizing and depositing iron. These iron-oxide deposits often contain high levels of arsenic. These communities form in water below 140° F/ 60ºC.
• Emerald-green mats color many of the runoff channels of hot springs and geysers here. Algae are the dominant life forms in these mats and contain chlorophyll, a green pigment that helps convert sunlight to energy. Some bacteria and archaea also grow in these mats, which form below 133°F \ 56ºC.
• Dark blackish-green mats form in even cooler water. An alga called Zygogonium forms these communities of mats and streamers.

Color within thermal water changes, in part, because temperatures and chemistry change. For example, in a hot spring the hottest water is closest to the source vent. As the water flows out, it gradually cools. This range of water temperature, called a thermal gradient, supports various thermophilic habitats.

Chemical composition also changes as water flows from thermal features, mixes with other water sources, and is diluted or concentrated. As temperatures or chemical compositions change, microbial populations—and the colors they create—shift to a location they favor.

Animals at Norris

Like other hydrothermal areas in Yellowstone, Norris provides a warm respite from winter for bison and elk. They can also find plants growing here year-round and water to drink.

Norris Geyser Basin is home to many insects associated with thermophiles. It also provides habitat for colorful dragonflies. Look for them in grassy areas near Crackling Lake in Porcelain Basin and Puff ‘n Stuff Geyser in Back Basin.

Killdeer nest on bare ground and will call in alarm if visitors are close by. Also, swallows fly over the basin catching insects to eat.

Protect Yourself & Protect the Features

Hot Water • Thin Crust
Hydrothermal features are fragile rarities of nature. Yellowstone preserves the largest collection of hydrothermal features on the planet. You have an unparalleled opportunity to view hot springs, geysers, mudpots, and fumaroles in a natural setting. In order to protect these rarities for future enjoyment, please:

• Stay on boardwalks or trails in hydrothermal areas that are officially marked and maintained; for your safety and to protect fragile formations.
• Keep all objects out of features. Rocks, sticks, coins, and other objects can choke off water circulation and end all feature activity.
• Smoking is prohibited in Yellowstone’s hydrothermal areas.
• For their safety, do not bring pets into Yellowstone’s hydrothermal areas.
• It is illegal to pick flowers or collect rocks or other objects. You may not collect any natural or cultural objects or remove, deface, or destroy any plant, animal, or mineral in Yellowstone National Park.
• Never approach or feed wildlife. Bears and other wildlife may appear in areas frequented by people—on trails, on boardwalks, and along roads. Do not approach animals and remain at least 100 yards (92 meters) away from bears and wolves, and 25 yards (23 meters) away from all other wildlife.
• Toxic gases such as hydrogen sulfide and carbon dioxide have been measured in some hydrothermal features. If you feel sick, leave the location immediately.

More on Day Hikes in Yellowstone

• 

  Yellowstone Backcountry Situation Report

  Current conditions for Yellowstone National Park trails & campsites.

• 

  Safety in Yellowstone

  Prepare yourself to safely enjoy wildlife, hydrothermal areas, and other features of Yellowstone National Park.

• 

  Bear Spray

  Read about this highly effective bear deterrent.