Closest entrances: 30 miles from the Old Faithful area to the West Yellowstone (west) entrance; 39 miles to the south entrance
Distance: 16 miles from the Old Faithful area to Madison
The hydrothermal fireworks continue as you move north along Grand Loop Road. At the next major stop, Midway Geyser Basin ★★, you’ll see two of the largest features of their type in the world. Excelsior Geyser used to erupt mightily in the 1880s—its bursts reached 300 feet and were as wide as they were tall. (Perhaps we’re lucky it’s rather quiet today.) The geyser still issues 5.8 million gallons of water per day into the Firehole River. Grand Prismatic Spring, at 370 feet across and 125 feet deep, is the second-largest hot spring on the planet. A boardwalk leads you close to the colorful spring, a bright blue pool ringed by striking bands of yellow, green, and orange thermophiles. But for my money, the best way to see it is from above, on the new-in-2017 overlook platform that delivers an encompassing aerial view of the spring’s grandeur. Reach it via a moderate, 1.2-mile (round-trip) hike from the Fairy Falls Trailhead.
About 8 miles north of Old Faithful, take the turnoff to Firehole Lake Drive ★. This 2-mile, one-way detour winds through another remarkable thermal area—and it’s much less crowded than Norris or Old Faithful. Great Fountain Geyser is one highlight: One of the six geysers that rangers publish predicted eruption times for, this fountain blows water 100 feet in the air, and the pulsing eruptions last up to an hour. White Dome Geyser features a giant sinter cone built up over hundreds of years; watch for its frequent 30-foot eruptions. And at Firehole Lake, stroll the boardwalk along a massive hot spring circled with travertine deposits.
Firehole Lake Drive will deposit you at the parking lot for Lower Geyser Basin ★, home to Fountain Paint Pot. A .5-mile boardwalk loops past the highlights, though what you’ll see depends on the season: Early in the year, the bubbling mud will be thin with abundant water, but later in summer it thickens to a muddy paste. Take care here—the reddish paint pots have tossed mud all the way to the boardwalk. Nearby Red Spouter sprang to life after the 1959 Hebgen Lake Earthquake. It, too, changes seasonally, from a hot spring and small, red-colored geyser in the spring to a mud pot in late summer to a steaming fumarole at year’s end.
The boardwalk swings west to a small geyser area with six spouters. Chances are excellent you’ll see at least a few go off: Spasm Geyser tosses up 20-foot-high spray frequently, and Clepsydra Geyser’s burbling is almost constant.
Know Your Bacteria
Even the most casual visitor can do some scientific sleuthing at the Fountain Paint Pot ★, learning to identify water temperature by observing the colors in the pots. The colors result from different types of bacteria that survive at specific water temperatures. Some are yellow until temperatures reach 161°F (72°C), above which the yellow bacteria cannot live. As temperatures approach boiling—199°F (93°C) at this elevation—pinks begin to appear.
As you continue toward the Madison Junction, consider a detour along Fountain Flat Drive, a left turn about 2 miles beyond Fountain Paint Pot. This scenic paved road ends a quarter-mile north of Ojo Caliente, after which it is open only to hikers and bikers. One mile south of the Firehole River Bridge, you’ll find the Imperial Meadows Trailhead. Park the car and head up the 4-mile trail to the 200-foot Fairy Falls.
The last side road you’ll hit before Madison Junction is also the best: The 2-mile Firehole Canyon Drive ★★. You’ll have to backtrack a bit after cruising the one-way, south-only road when coming from this direction, but the payoff is worth it. The road winds through a super-sheer gorge along the Firehole River, abutting 7,500-foot National Park Mountain and passing 800-foot-thick lava deposits. Stop for a peek at the tumbling cascade of 40-foot Firehole Falls before reaching the cherry on top: a swimming hole ★★ near the end of the road. This is one of the only places in the park where it’s safe to splash around, and the cool water can’t be beat on a sweltering August afternoon.
Depending on your driving skills and your tolerance for slow-moving vehicles, there is no substitute for a self-driven park tour. For $45 a day (less if you keep it longer), gadget fiends can rent dashboard-mounted GPS units from GaperGuide (www.gaperguide.com; tel. 307/733-4626) with prerecorded audio keyed to locations in both Yellowstone and Grand Teton. You can pick up and drop off units in every Yellowstone gateway town, plus Jackson, Teton Village, and Moran.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.