Nestled in the woods just outside the town of Redstone is a collection of giant, red, conglomerate sandstone boulders. The area sits among stands of Aspen, and offers the quintessential Colorado bouldering experience. To get there drive south from Carbondale on Hwy 133, to the first entrance to Redstone. Follow this until you are almost to town, and then take a left on an unmarked dirt road. A trail heads south and then east to the most popular spot.
The climbing here is mostly for the more advanced, though there are a handful of easier problems in the V0 to V3 range. Seasoned pebble wrestlers will find enough challenges to keep them coming back for some time.
If you do happen to climb everything here, be sure to stop by the River Boulders. It's the same kind of rock, but the blocks are located on the shores of the Crystal River. Just look for the obvious pullout between the two Redstone entrances. As an added bonus if it's hot out you can always cool off in the river!
More info is available in Rifle Mountain Park and Western Colorado Rock Climbs and SplitterChoss.com.