The town centre and Tyholmen are easily walkable. Local ferries connect the harbour with Merdø and several other islands in the archipelago — timetables are available from the harbour office and run frequently in summer, less so in winter.
Tromøya is accessible by road across the bridge. Cycling is a good way to explore both the island and the mainland coast around Arendal. Bicycle rental is available in town.
For the Raet National Park, the best access is by kayak or small motorboat — rentals are available from operators near the harbour.