Distance: 2.2 miles (3.5 km) round trip
Trailhead Elevation: 7,600 feet (2,315 meters)
Sentinel Dome Elevation: 8,100 feet (2,470 meters)
The Sentinel Dome trail is the red line on the map, beginning at the green hikers and ending at the two pink balloons.
The green line is the trail to Taft Point. Savvy hikers frequently combine Taft Point and Sentinel Dome into a single expedition, since they share a trailhead and since the Pohono Trail - the purple line on the map - provides a connector route with its own memorable view over the rim of Yosemite Valley.
The dark blue line is Glacier Point Road. The Taft Point/Sentinel Dome trailhead is only a few miles from Glacier Point itself; you can see it here by scrolling a couple inches to the right.