Mary Mountain Trail

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Mary Mountain trail is the most popular hike in the Hayden Valley region of Yellowstone and one of the best ways to see the valley and its abundant wildlife from up close. The trail stretches for a little over 21 miles across the valley and can be approached in several different ways- as a shuttle through hike or an out-and-back type of deal, starting from one of the two trailheads located along Grand Loop road.  

PRECAUTIONS 

Mary Mountain trail is closed in the winter/spring seasons, from March 10 to June 15, due to a high grizzly bears activity in the region. In fact, grizzlies frequent the area throughout the year (that is when they are not hibernating :) or when we’re around to spot them) and are by far the most dangerous element of the hike. People have been attacked by bears and most recently, in 2011 a grizzly female defending her cubs killed a hiker near Mary Mountain. Do not approach bears under any circumstances (you CANNOT outrun these giants) and carry bear spray at all times. 

Other than bears, there’s a good chance of finding bison along the trail as they use the beaten path to move about the valley. When encountered, give them enough space and get off the trail to pass them. 

The trail can be muddy at spots, especially early in the summer. We hiked it in late August both occasions we did it and there were impassable sections where we had to steer a little off the trail to pass. 

TRAILHEAD 

As I mentioned before, there are two trailheads, both offering a small parking turnaround but no facilities of any kind. One, named Marry Mountain East trailhead, is located where Alum Creek meets Yellowstone river, 4 miles from the Canyon Junction.  
 

And, on the other side, the Mary Mountain West trailhead is located 9.5 miles from Old Faithful Junction, by the Porcupine Hill Geyser 

You can park alongside the road in both locations, but come early as it’s quite a popular hike and you may find it difficult to park close to the trailhead later in the day.  Plus, an early start means more animals on the trail (again, if you’re not us).

THE HIKE 

We started Mary Mountain hike at the East trailhead, close to Canyon Campground where we camped the night before. Starting from this point, it will be closer to reach the famous bends in the Alum Creek the trail follows, but further to Mary Lake (around 12 miles each way). We hiked to the Highland Hot Springs area and turned back at that point, making it a 20 miles round trip hike, which took us around 9 hours to complete. While the elevation change on Mary Mountain Trail is minimal, it’s the distance and lack of shade that make it somewhat strenuous.  

Only a few miles into the valley, we’ve encountered big herds of bison grazing on the green patches and nursing their young. At one spot, there were at least a hundred of themno more than 100 yards from the trail. Speaking of, the trail is sometimes hard to follow, as bison make their own paths, seemingly to confuse hikers like us. There are bright orange stick markers every 0.5 mile or so, soit’s a good idea to take binoculars with you to spot them from the distance. Furthermore, bison knock these down sometimes too, it's a good idea to take a picture of the map posted at the trailhead to be sure you're going the right way.  

We also spotted a grizzly bear in the distance later that day, so they are definitely there:) 

Sometimes, you meet the other kind of hiker on the trail and we suggest you give them right of way. 

The two thermal areas we passed(Violet Springs and Highland Hot Springs) were equally fascinating and, with a little bit of luck combined with an early start, you can have them all for yourself.

We spotted a few small hot springs, a mudpot and numerous fumaroles, all nested in multicolor (thanks to heat tolerating algae) sand basins. When we reached the 10-mile marker, we decided to turn back at this point. 2 more miles into the hike and we would reach Mary Lake, but hey, we can always do that from the western trailhead the next time we visit Yellowstone :). On our way back, we stopped briefly to watch bison minding their own business. Late August is an interesting time to observe their behavior, as males start to “show-off” (by wallowing in the sun-baked dirt) and spar for dominance in the herd. 

What a hike that was! Hayden Valley with its wildlife and breathtaking, grand vistas, is one of the best places to get up close to in Yellowstone National Park.