The island has a single ring road that runs around the outside — except for the wild west coast, which has no road at all. A small public bus links Uehara and Ohara every hour or two during the day, and most accommodations will arrange airport-style transfers from the ferry pier.
A rental car is by far the easiest way to explore independently; cars and scooters can be hired at both ferry ports. Inside the national park, vehicles must stick to the marked road. Drive slowly, especially after dark: the Iriomote cat is hit by cars far too often.