Aach is a small town in the German state of Baden-Württemberg. Being situated close to Lake Constance and the Swiss border, it is mostly known for the Aachtopf — Germany's biggest natural spring in terms of production.
In 1499 battles of the Swabian War took place right before gates of Aach. Only 26 years later, in 1525, the Peasants' War reached Aach, when region's aristocrats flew from the uprisings to the city, whereupon it was occupied by the rebel peasants. However, the uprisings were thrown down quickly by September 1525.
On March 25, 1799 there was a battle in Aach between Austria and France in the Napoleonic Wars. After Austria's defeat in the Third Coalition 1805, Aach came to the Grand Duchy of Baden, which joined the German Empire in 1871.
Aach has formed a cooperation with the nearby City of Engen sharing some of its administrative domains.
Aach has a city council with twelve seats. The last elections in 2004 brought three seats for the CDU, three seats for the SPD and four seats for independent voters' associations. Aach's mayor is Severin Graf (CDU).