At Yellowstone National Park there are around 500 geysers and over 10,000 thermal features! There are more geysers at Yellowstone than anywhere else on Earth. One of the best walks to see many of the pools, springs and geysers is the Upper Geyser Basin right near the Old Faithful Inn. I love this map of the area:
When we visited in 2014, Craig and I walked the whole Upper Geyser Basin, past Morning Glory Pool, through the woods to Biscuit Basin. It took about three hours round trip. We stopped to take pictures, videos and to sit near the Firehole River for a snack. Be sure and take your bear spray. We did not see many people past Morning Glory Pool.
There will be geyser eruption times posted at the Old Faithful Inn and the Visitor Center. There is also an NPS App you can download that will give you several possible eruption times. Sometimes, you will luck out while walking and see a group of “Geyser Gazers” that may be waiting by a certain thermal feature. They keep the rangers up to date on what might be ready to erupt. We got to see Beehive Geyser shoot 200 feet in the air! The rangers also give free walks and talks around the geyser basins during the day and evenings.
Do not forget Norris Geyser Basin, Black Sand Basin, Midway Geyser Basin, the Lower Geyser Basin and Firehole Lake Drive. West Thumb Geyser Basin is also unique because it is next to Yellowstone Lake. I love the Fishing Cone hot spring where in the past people would catch a fish in the cold lake and then cook it in the spring! Be careful! When you get past Morning Glory Pool, you are able to walk right next to some of the thermal features. The boardwalks can also get very crowded at peak times. Near Grand Prismatic Spring was usually packed. Stay on marked trails. What geysers have you seen erupt at Yellowstone? Sometimes you will catch a surprise eruption!