Closest entrance: 22 miles from West Thumb to the south entrance

Distance: 17 miles from West Thumb Geyser Basin to Old Faithful

The high-altitude road west of West Thumb crosses the Continental Divide twice in this section, the second time at 8,262-foot Craig Pass. At both points, precipitation falling on the east side of the divide eventually flows to the Atlantic Ocean, and anything falling to the west is Pacific Ocean–bound. An interesting phenomenon takes place at Isa Lake atop Craig Pass. It has both eastern and western drainages and ends up in both the Pacific Ocean and the Gulf of Mexico. Amazingly, because of a gyroscopic maneuver, the outlet on the east curves west and drains to the Pacific, and the outlet on the west curves east and drains to the gulf.

About 3 miles south of the Old Faithful area, an overlook grants a peek at Kepler Cascades, a 150-foot stair-step waterfall on the Firehole River. This is also the trailhead for one of Yellowstone’s best easy day hikes, the 4.8-mile (round-trip) hike to Lone Star Geyser ★★. The trail winds along the Firehole River to the geyser’s cone (bikes are allowed most of the way, and it’s also a fun cross-country ski route), where a 30- to 45-foot plume erupts every 3 hours or so (a logbook on site should tell you when the last eruption occurred). Wide meadows and sunny riverside basking rocks make waiting for the next spout more than pleasant.

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.