In the world of Test Drive Unlimited, the player is able to drive both on-road and off-road in free-roam mode, challenging any real life racers they encounter. The roads are modeled after satellite images of the island of Oʻahu. The terrain differs from rainforest and mountains to sandy beaches and Hawaiʻi’s capital city, Honolulu. It is worth noting however, that other built-up areas on the island are not represented. It is possible to drive on small islands outside of the main island, and even drive underwater.