The Obsidian Trail 
Location: California   Length: 27 min      56k   300k   700k         56k   300k   700k
In the shadow of Mt. Whitney lies California's Owens Valley, the deepest valley in North America. Its contrasting environments include snow-capped spires, desert valleys, volcanic moonscapes, and verdant marshlands. Archaeologists for thirty years have recorded petroglyphs, pottery, and bone, wood, and stone tools, piecing together the lifeways of the region's original inhabitants. With advances in analysis of obsidian (black volcanic glass), they are re-examining what ancient arrowheads, points and flakes can reveal and are learning some surprising things.