Picture Yellowstone as the figure eight. The northern circle has the most animals and the southern circle has mostly geysers including Old Faithful. They will tell you when OF is going to erupt next so you won't miss it. Stay at Grizzly, you won't regret it. If you have kids with you, they will thank you. Shop in town and pack warm clothes..it will be cold at night..leave your rig at the campground and take the car. There's many places that prohibit RVs within the park and you'll miss lots of interesting stuff if you have to stay on the main roads.....Dennis