Mastodon Boulder is one of the largest boulder problems located on Main Hill of the Pipestone bouldering area. Characterized by a large crack on the left side, Mastodon Boulder offers many route options with varied grades.The Approach is only a quick hike away along the well established four-wheeler trail. These uniquely placed boulders are situated between sage, cactus and pines, and offer great “off season” climbing opportunities during those milder winter days. One to two pads are required here, but bring more if you have them. Bring spotters you trust.