The town of Arendal is the administrative center of the municipality and also of Aust-Agder county. Other villages in the municipality include Tromøy, Rykene, Eydehavn, Strengereid, Kongshamn, Kilsund, and Hisøy.
In the middle of the town centre is an area with wooden houses dating back to the 17th century. This area is called Tyholmen, and is what is left of buildings from before the 19th century. The inner harbour of Arendal is Pollen, where the fish market, pubs, and restaurants are located.