Aarwangen is the third largest municipality in the Bernese region of Oberaargau and was originally a settlement near a crossing over the River Aare. Aarwangen had a roofed wooden bridge as far back as the 16th century. The river was an important trade route until the 18th century saw in the era of road and railway transport. Aarwangen was on the merchandise trading route between the Burgundians (in western Switzerland) and the Alemanni (in eastern Switzerland). The Oberaargau villages were Alemanni settlements.

Aarwangen Castle was built by Kyburg nobility in the 13th century to defend the important river crossing. A total of 75 governors resided there throughout the centuries. This castle of regional significance has been the seat of the Bernese cantonal authorities for almost six centuries. The former moated castle is part of a distinctive complex restored in the baroque style and dominated by the early Gothic main tower. The nine-storey, uninhabitable main tower is a striking feature of the castle. It is enclosed by housing on three sides.

Aarwangen’s centre boasts several stately old houses. A prominent example is the «Tierlihaus» near the railway station, a stately half-timbered manor built for a menagerie owner in 1767. Its façade is embellished with one-of-a-kind murals of exotic animals, birds of prey and oriental city scenes.

Other Aarwangen attractions are the shaded river lido by the Aare, the river and town views and views of the Muniburg hill to the west and a bike ride along the Aare banks with shuttle bikes; mountain bikes that can be adapted to ride on water.