From Las Vegas: Take I-15 to the Hurricane exit, then follow Utah 9 to Toquerville; take a right onto Utah 59 continuing until you come to Springdale. Park in Springdale and take the Shuttle to the park (or take your chances on parking by the Visitor Center).
From Salt Lake: Take I-15 to the Hurricane exit (Utah 9). Follow Utah 9 to Toquerville and turn on Utah 59. Park in Springdale and take the Shuttle to the park.
From Arizona: Take US-89 and/or US-89A to Kanab, Utah. Continue North through Kanab and turn onto Utah 59 at Mt. Carmel Junction. Go through the park (paying the park entrance fee) and park in Springdale, where the Shuttle will whisk you away to the visitor center.
From Bryce Canyon: Head West on the highway out of Bryce until it meets Utah 89 outside of Panguich. Go South on Utah 89 to Mt. Carmel Junction, then West on Utah 59 through the park to Springdale to catch the Shuttle...
From North and East: From the direction of Colorado, drive West on I-70. For a scenic tour (and an extra couple of hours), I highly recommend exitting to Utah 24 just West of Green River, Utah, driving to (and then taking) Scenic Utah 12 past Bryce Canyon (follow the Bryce Canyon directions from there). Or, you can zoom out I-70 to I-15 and head South (and follow the Salt Lake directions).
Fees: ~$20 per car, or (better) $50 for a National Parks Pass
Lodging: Zion Lodge is located in the canyon. There are many excellent places to stay in Springdale just outside the canyon, where a Shuttle makes frequent stops to take you into the park.
Camping: There is one campground in the park (often full during the tourist season). A couple of private campgrounds and RV Parks exist in the Springdale area as well. There are a couple of BLM campsites further outside of town.
Food: The Zion Lodge has a fast-food concession as well as a restaurant. Springdale offers a good selection of restaurants, though most are pricey.
Information: The park Visitor's Center is conveniently located at the mouth of Zion Canyon at the junction of the Springdale and Zion Canyon Shuttle routes. Most of the Visitor's Center opens at 8am, but the backcountry desk window opens at 6:30am. Aside from a bookstore with a good map selection and a nice children's selection, there are a large number of Rangers on duty to help out. Rangers lead hikes throughout the day, usually meeting at the appropriate trailhead.
Park Facilities: There are several sections to Zion. Zion Canyon offers the tourist a scenic drive (Shuttle only as of 2000) which winds up the canyon, with lush vegetation contrasting with towering canyon walls. The East side of the park offers a drive and hikes through a sculpted sandstone desert. Kolob Canyons is a remote section of the park North and West of the main park, and offers a scenic drive through less intimidating (though more rugged) canyon country than that of the main canyon. Lastly, Kolob Terraces offers backcountry hikes and canyoneering adventures. For handicapped tourists, the Canyon Shuttle system is fully handicapped-accessible with kneeling buses and wheelchair lifts; the Riverside Walk at the head of the canyon is paved and accessible with effort or assistance; the Lower Emerald Pools trail is also paved and accessible with strong assistance; and the Pa'rus Trail, leading from the Visitor's Center to the Canyon entrance (about 1.7 miles) is fully accessible.
Trails: Trails in the park vary widely in length and difficulty. Even within Zion Canyon, there are trails up to 5 miles with steep elevation changes. Trail surfaces also vary; several are paved; others are hard-packed dirt or are cut into rock. Some trails have extreme dropoffs on narrow ridges. Outside the Zion Canyon section of the park, all trails are rough, and some require extra skills beyond trail hiking. See the Tour Guide for more details on several trails.
Bryce Canyon: Bryce Canyon is only a couple of hours away, and an excellent destination if you have an extra day to get away. If you're a photographer or scenic lover, make sure you're there for a sunrise...
Joshua Tree National Natural Area: If you aren't from California, chances are you've only seen Joshua Trees in photographs (or Springdale, where a couple of residents have planted them). Just to the SouthWest of St. George is a whole forest of them, managed by the BLM. Your best bet is to stop off at the BLM station in St. George (Bluff Street exit) for directions - they'll give you the back route through town and a local Indian Reservation. By the time you wind through the backroads, it's about 2 hours from Zion.
Valley of Fire State Park (Nevada): Just 30 miles from Las Vegas, and somwhere under 3 hours from Zion, is the Valley of Fire State Park. This magnificent little(?) park is a wonderland of sandstone erosion. Several arches dot the park, but the main attraction is the sheer oddity of the erosion patterns, which appear much more eaten away than at other locations such as Arches National Park.
Coral Pink Sand Dunes State Park: This park caters somewhat to the ATV crowd, but offers a pedestrian-only section as well, through pinkish red sand dunes.
Other Destinations: Other places close to Zion which I have not yet explored include Snow Canyon State Park, Cedar Breaks National Monument, and Pipe Springs National Monument. Oh - there's also the casinos of Las Vegas 3 hours away.