Impounded behind Shasta Dam on the Sacramento River, Shasta Lake is the centerpiece of the Whiskeytown-Shasta-Trinity Natl Rec Area. Its waters back up the Sacramento River as far as Lakehead. The two other major arms are the McCloud River Arm and the Pit River Arm. There are a few islands in the lake and many peninsulas projecting into it. Shasta Lake is about 10 miles north of Redding in Shasta County.