Hike Distance: 6.6 miles (10.5 km) out and back or 5.5 mile (9 km) loop
Trailhead Elevation: 7,000 feet (2,100 meters)
Total Elevation Gain: 100 feet (30 meters)
The trail (marked in red) is mostly flat and smooth, but it does have a few obstacles: you'll have to ford Bridalveil Creek (the green line) just before you reverse direction and start heading toward Bridalveil Campground; and if you do a loop instead of an out-and-back, you'll have to hike along Glacier Point Road, which was apparently built before shoulders were invented, to get back to your car.
The trailhead (see the kong-sized green hikers) is also the trailhead for the Ostrander Lake trail. If you detour from the red line by turning left at the first fork, you'll stay on the Ostrander trail. If you turn left at the next fork, just across Bridalveil Creek, you'll have another chance to catch up to the Ostrander Lake trail, and you'll also be able to fork off to various back-country lakes or to Chilnualna Falls and Wawona.