Union Falls Trail - Countdown: 10 Days

August 15, 2012 Posted by: KG

Many of the 3 million visitors to Yellowstone go and see the tallest falls in the park, Lower Falls on the Yellowstone River. However, lesser known but just as impressive is the second tallest falls. Union Falls, which derives its name from the fact that two rivers join just at the edge of the falls, is a spectacular 250 feet tall.

Union Falls is less visited than other waterfalls in Yellowstone due to it being in the backcountry. It is a long day hike, or a relatively straighforward overnight trip. Either way, don't forget to bring a bathing suit!

To get to the trailhead, follow the Grassy Lake Road. If you are coming from the east, you will start at Flagg Ranch and pass through the John D. Rockefeller, Jr. Memorial Parkway. You will end up passing into the National Forest before you get to the trailhead. From the west, you will also travel along the Grassy Lake Road, but if you enter the Parkway, you have gone too far. The Grassy Lake Trailhead is on the western edge of Grassy Lake Reservoir on the north side of the road. Also, please remember that the Grassy Lake Road is not open year-round, and is difficult traveling all year. A high clearance vehicle is highly recommended.

The trail begins on the west side of the parking lot. Less than a half mile in you will cross the boundary into Yellowstone National Park. About a mile after that, there is a large stream crossing. Remember to bring and extra pair of shoes, preferably ones that strap on (not flip-flops) because the water is swift. The water is high and can be dangerous in early season, but by mid-July, crossing is pretty straight forward.

Stream crossing on the Union Falls Trail (Photo Credit: K. Greenwood)
Stream crossing on the Union Falls Trail
Photo Credit: K. Greenwood, NPS

After the river crossing, the trail winds through a very pretty forest with lots of fun surprises for those hikers who know what to look for (think huckleberries!) The elevation gain along the whole trail is approximately 600ft. There is one long section of downhill on the way out, which will feel much longer on the way back, but this is the only significant challenge along the trail.

The first campsite is at about 6 miles, the other is another half mile. To reserve a campsite, visit a ranger station in Yellowstone before you begin your hike. Campsite reservations may be made 48 hours in advance. The closest permit office to this area is at the Yellowstone South Entrance.

From the campsites, continue along the trail another mile. You will come to a horse hitching post and there is an unmarked trail that leads to the left. Following this trail for another half mile will bring you to Ouzel Pool (also known as Scout Pool), a thermally heated swimming hole with a small waterfall. Temperatures fluctuate between heated swimming pool and hot tub. The area under the waterfall is deep enough to swim around and even get a waterfall massage!

Waterfall Massage (Photo Credit: K. Greenwood, NPS)
Waterfall Massage at Ouzel Pool
Photo Credit: K. Greenwood, NPS

If you do not follow the trail leading to Ouzel Pool, continue along the main trail for another half mile and you will come to beautiful Union Falls. There is a great overlook where the entire falls is visible and you can feel the wind and spray from the falls. It is also possible to follow a steep trail down to the base of the falls. This area is very wet and slippery, so watch your footing. Also, the spray from the waterfall will definitely get you cold and wet.

Union Falls (Photo Credit: K. Greenwood, NPS)
Union Falls
Photo Credit: K. Greenwood, NPS

The trip to Union Falls is a rewarding adventure in a quiet corner of Yellowstone. Like many of the trails that begin in the John D. Rockefeller, Jr. Memorial Parkway, visitors are rewarded with serene trails and unexpected surprises.

- KG

Last updated: August 15, 2012

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