The speed limit is 45mph, except in Yosemite Valley, where it drops to 35mph. Truth is, traffic will make you slow down anyway. Glacier Point Rd and Tioga Rd are closed in winter.
The free, air-conditioned Yosemite Valley Shuttle Bus is a comfortable and comparatively efficient way of traveling around the park. Buses operate year-round at frequent intervals and stop at 21 numbered locations, including parking lots, campgrounds, trailheads and lodges. For a route map, see Yosemite Today.
Free buses also operate between Wawona and the Mariposa Grove (spring to fall), Yosemite Valley and Badger Pass (winter only), and the Tuolumne Meadows Shuttle between Tuolumne Lodge and Olmsted Point in Tuolumne Meadows (usually mid-June to early September).
Two fee-based hikers’ buses also travel from Yosemite Valley. For trailheads along the Tioga Rd, catch the Tuolumne Meadows Tour & Hikers’ Bus (209-372-1240; Jul-early Sep), which runs once daily in each direction. Fares depend on distance traveled; the trip to Tuolumne Meadows costs $14.50/23 one way/round-trip. The Glacier Point Hikers’ Bus (209-372-1240; one-way/return $20/32.50; mid-May-Oct) is good for hikers as well as for people reluctant to drive up the long, windy road themselves. Reservations are required.