Hiking from the Valley to Glacier Point and Panorama TrailThe most popular trailhead is near the Swinging Bridge. The trail to Glacier Point is called "four mile trail". The name is misleading: its length is about 7.5kms long (about 2h 30'). A further 2 kms take you to Sentinel Dome via the Pohono trail (1 hour roundtrip). Retracing your steps to Glacier Point, you can descend via the Panorama Trail via Illilouet Falls (3.3kms, 1 hour) to the trail junction (6.4kms, 2 hours) to the Nevada Falls (8.2kms, 2h 30') to Vernal Falls to the Happy Isles trailhead (about 13kms from Glacier Point to Happy Isles, about 3h 30' total).
The grand total is you hike the four-mile trail, the Sentinel Dome trail, and the Panorama trail is about 30 kms and estimate 8 hours at a brisk pace.
A free shuttle bus takes you back to the Swinging Bridge area.