Summary 
| Difficulty | 3 Intermediate |
| Length | 5.5 miles round trip |
| Starting Elevation |
8050 feet |
| Cumulative Elevation Change |
+600, -600 round trip |
| Navigation | Road, marked trail, and map |
| Time | Most of a day |
| Season | December through April |
| Snowmobiles Use | Not permitted [Please report illegal use of snowmobiles in this area.] |
| USGS Topo | 7.5' series, June Lake, Mammoth Mountain |
| Start | Highway 395 at Obsidian Dome Road, 3.8 miles south of June Lake Junction (June Lake Loop South Entrance) and 11.7 miles north of Mammoth Junction (junction of Highways 395 and 203). |
Description
The variety of terrain on the tour around Obsidian Dome makes it one of the most interesting tours in the Deadman Summit area. You even have the opportunity to ascend the dome and explore the mile-diameter rocky plateau that is its summit.
Mileage Log
Numbers in parentheses
correspond to mileage points on map
Waypoint 1 -2
Miles: 0.0 - 1.0
Elevation change: +150
From the trailhead (1), ski southwest on Obsidian Dome Road for 1.0 mile until you reach a road junction (2). The fork to the west (right) is part of the Hartley Springs Campground Loop tour. The tour described here continues on the fork to the east (left).
Waypoint 2 - 3
Miles: 1.0 - 1.5
Elevation change: +150
Continue on the fork to the east (left) and shortly turn south for a total of 0.5 mile until you reach a very obscure road junction (3) where the obvious road turns southeast (left). At this point you are very close to Obsidian Dome and on its west side.
Waypoint 3 - 4
Miles: 1.5 - 1.6
Elevation change: +0
Ski southeast (left) on the obvious road for about 100 yards until you reach a road junction (4). The east (left) fork is a narrow road that climbs at a very steep angle along the side of Obsidian Dome and then onto the plateau that is the dome's summit. Refer to the Obsidian Dome tour for details. The loop tour continues on the southern-most (right) fork.
Waypoint 4 - 5
Miles: 1.6 - 2.5
Elevation change: -200
Gradually descend the southern-most (right) fork, weaving south, for 0.9 mile until you reach the south side of the Obsidian Dome (5) where you will find yourself on a bench alongside Glass Creek.
Waypoint 5 - 6
Miles: 2.5 - 3.6
Elevation change: +100, -200
Ski counterclockwise on the bench around the south side of Obsidian Dome for 1.1 miles until you reach a flat plateau on the dome's east side (6). In this section, expect to be hemmed in between the steep slopes of the dome and Glass Creek.
Waypoint 6 - 7
Miles: 3.6 - 4.0
Elevation change: +50, -50
Continue to ski counterclockwise around Obsidian Dome for 0.4 mile until you reach the lip of a large gully (7).
Waypoint 7 - 8
Miles: 4.0 - 4.8
Elevation change: +200, -50
Descend north to the bottom of and climb north out of the gully to the top of a small, flat ridge, beyond which you ski northwest and then west for a total of 0.8 mile until you reach Obsidian Dome Road (8). If you are lucky, you will pick up a marked trail, possibly groomed, in this section.
Waypoint 8 - 1
Miles: 4.8 - 5.5
Elevation change: -100
Turn northeast (right) onto Obsidian Dome Road and follow it for 0.7 mile until you reach the trailhead (1).
