In Yellowstone the winters are really cold and they get sometimes 6 feet of snow.
It's heard to get to Yellowstone because it's up in the mountains.
Native Americans used obsidian to make arrows because they stayed sharp.
Petrified wood is the wood that is covered in ash and it creates stone.
There are geysers in Yellowstone and it can shoot up water in the air.
They found so many things in Yellowstone that are dangerous.
If you go inside a hot spring you will die from the heat.
Some geysers and hot sprigs can be acidic.
the geysers are also really hot and the temperature is about 400 degrees farenheight.