Longyearbyen itself is small enough to walk in twenty minutes end to end. The airport, the town centre, UNIS, and the museums are all within easy walking distance, and most visitors never need a vehicle in town.
Beyond the town boundary, things change entirely. There are no roads connecting Longyearbyen to anywhere else on Svalbard — the archipelago has no inter-settlement road network. Travel outside town is by snowmobile in winter, boat in summer, or on foot with a guide. All three require planning and, for independent travel outside the town boundary, you must carry a rifle due to polar bear risk; most visitors hire a guide rather than deal with the rifle permit.
Taxis are available for the 3 km run to the airport or the 4 km trip to the Svalbard Global Seed Vault. Local tour operators run minibuses for excursions. Snowmobile rental requires a valid driving licence; guided snowmobile safaris are the most popular option for winter visitors. In summer, RIB boat tours, kayaking, and hiking trips into Adventdalen are the main alternatives to walking.