Fairy Falls Trail
As you're walking up to the Fairy Falls Trail, it's like your stepping onto another planet. Before you even get to the trailhead, you're surrounded by hissing steam vents and pools of vividly colored water. Although the steam looks relatively harmless as it drifts lazily up into the sky, you know that fumaroles, or steam vents, are actually the hottest volcanic features in Yellowstone National Park. Small amounts of water heat to boiling temperatures underground, which causes the steam you're seeing right now.
You cross the small, wooden Firehole River Bridge, which got it's name from the river you're passing by. On the other side, there are multicolored hot springs. You marvel at them briefly but decide not to stay too long. The Fairy Falls trail is 5.1 miles round trip. Although the walking is relatively easy and there's a nice breeze, you want to give yourself plenty of time to stretch your legs as you wind throughout the mountains.