Treungen lies beside the southern end of lake Nisser, and the Telemarksveien (Norwegian National road 41) passes through the village northwards towards Vr�dal and southwards towards �mli in Aust-Agder. The state highway was widened after the Treungen railway was dismantled in 1967. Treungen was the railway terminus. Telemark Bilruter runs a bus route between Arendal and Seljord, and this route replaces the abandoned rail connection to Arendal.
Treungen is split into two by lake Nisser and in the middle of the village is Tveitsund bridge, a fine stone bridge adorned with concrete columns. The bridge was protected as a cultural monument in 1999. It's small, and traffic is controlled by lights. The inn is a building characteristic of Treungen's early days as a travel interchange between road and railway. The inn is in the Jugendstil of architecture, adorned with classical columns.
Throughout its history, Treungen has been closely linked with the town of Arendal and Aust-Agder county because lake Nisser was a part of the Arendal waterway and had its outflow through Nidelva. When timber was floated downriver, Treungen was an important hub. The timber came here along lake Nisser before being sent on its journey to Arendal
