The largest size is the 24” to 36” boulders. These are typically used in conjunction with the 12” to 24’ boulders to build medium and large retaining walls. We do also keep a stock of pudding stones and feature stones if you are looking for something special in an accent boulder. Boulders are sold individually, or by the cubic yard. One cubic yard weighs approximately 1 ½ tons or 3,000 lbs.