The main Zion Canyon is closed to cars. There is a very good shuttle bus system for visitors.
Think of this as a guided tour bus within the park. Starting at the Zion Canyon Visitor Center, this shuttle takes visitors
on a scenic ride up Zion's main canyon, making several stops at interesting locations and trailheads, including the Zion Lodge,
the Grotto (start of the Angels Landing hike), Weeping Rock, and the Temple of Sinawava (close to the Zion Narrows where the steep canyon walls converge).
Since shuttles come regularly, you can get off at any spot, explore, and then get on the next shuttle.