Gigapixel view from the summit of Glass Mountain (elev. 7,620') at the eastern end of the Medicine Lake Volcano in California.  The mountain is an uncommon feature on earth, comprised of a large obsidian flow that erupted around 900-1000 years ago from 13 different vents.  The obsidian varies from familiar black shiny outcroppings to obsidian froth.  While most obsidian is found within the edges of the flow, this summit area Glass Mountain is comprised of dacite.  The trek here is nothing but a constant up & down jumble of trenches & hills of sharp glassy rock.  No rock collecting allowed.  Summit views of Mount Shasta, Mount Hoffman, Lyons Peak, Red Shale Butte, Mount Dome, Medicine Lake to the west, & the Klamath Basin to the north.

Gigapixel panorama (1.070 gigapixels), 223 photos, 46264x23132 pixels