Yosemite National Park
Distance: 5 miles Time: 2 hours Type: Round trip
I write more about Yosemite in the Glacier Point hike (a full day's hike up to Glacier Point and down again from the Valley floor - see here).
This hike is a shorter (and flatter) walk from Glacier Point Road which offers superlative views of the Valley below, including from the 'peak' of Sentinel Dome. I completed this walk on a visit to Yosemite in August and would recommend it if you have limited time in the Park or want to squeeze in a shorter walk while touring the rest of the Valley.
The trail-head is located at Sentinel Dome and Taft Point Trailhead car park. Being a circular route, you can hike in either a clockwise or anticlockwise direction (we chose to do the latter, as to gain Sentinel Dome toward the start). The walk is not too strenuous, although be aware it does follow cliff edges so keep your eyes on children and dogs! The views to the west are perhaps the best, with El Capitan and the Cathedral Spires framing the entrance to the Valley. To the north you can see across to Lower and Upper Yosemite Falls (both of which were dry when we visited in August).
For a longer walk, you could use the shuttle to reach the trail-head, complete most of the circuit in an anticlockwise direction as described and then link up with the Pohono trail to the west, which continues for around 9/10 miles down to the Valley floor at Bridalveil Falls. Alternatively, you could complete the same route in the opposite direction if you fancy a climb and more of a challenge.
Here is a link to a map of the park: