The pumice pits is a great place to ride that is close to Idaho Falls. There isn't really trails here but just a fun area to go out and play around. There is lots of hills to climb, whoops, jumps, berms, and just fun play around riding. We love to come up her after work or if we just have a couple of hours to kill. Its nice because its only about ten minutes from Idaho Falls. Be careful when you are riding here until you get used to the area because there is lots of cliffs and sudden drops that could be dangerous if you don't know where they are. We usually like to come out here when it is still too cold in the mountains because there is usually less snow. We just went today 3-9-13 and it was still a little too snow covered, probably another week or so and it will be great. If you are looking for some good climbs close to home this is the place for you.
Here is the GPS to get to the pumice pits, if you need to download the gps file just click on the link above the map and it will take you to a site where you can download it. Enjoy!