Aarau (ˈaːraʊ, ˈɑːræu̯) is a town, a municipality, and the capital of the northern Swiss canton of Aargau. The town is also the capital of the district of Aarau. It is German-speaking and predominantly Protestant. Aarau is situated on the Swiss plateau, in the valley of the Aare, on the river's right bank, and at the southern foot of the Jura Mountains, and is west of Zürich, south of Basel and northeast of Bern. The municipality borders directly on the canton of Solothurn to the west. It is the largest town in Aargau. At the beginning of 2010 Rohr became a district of Aarau. The official language of Aarau is (the Swiss variety of Standard) German, but the main spoken language is the local variant of the Alemannic Swiss German dialect. The old city of Aarau is situated on a rocky outcrop at a narrowing of the Aare river valley, at the southern foot of the Jura mountains. Newer districts of the city lie to the south and east of the outcrop, as well as higher up the mountain, and in the valley on both sides of the Aare. The neighboring municipalities are Küttigen to the north and Buchs to the east, Suhr to the south-east, Unterentfelden to the south, and Eppenberg-Wöschnau and Erlinsbach to the west. Aarau and the nearby neighboring municipalities have grown together and now form an interconnected agglomeration. The only exception is Unterentfelden whose settlements are divided from Aarau by the extensive forests of Gönhard and Zelgli. Approximately nine-tenths of the city is south of the Aare, and one tenth is to the north. It has an area, , of . Of this area, 6.3% is used for agricultural purposes, while 34% is forested. Of the rest of the land, 55.2% is settled (buildings or roads) and the remainder (4.5%) is non-productive (rivers or lakes). The lowest elevation, , is found at the banks of the Aar, and the highest elevation, at , is the Hungerberg on the border with Küttigen. A few artifacts from the Neolithic period were found in Aarau. Near the location of the present train station, the ruins of a settlement from the Bronze Age (about 1000 BC) have been excavated.
Stéphane Joost, Idris Guessous, Murielle Bochud, Joël Chételat, Fred Michel Paccaud