Aach () is a small town in the German state of Baden-Württemberg (the region of Hegau). 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. The town was originally twinned with the region of Colmnitz, but following the integration of Colmnitz into Klingenberg, Saxony the town is now twinned with Klingenberg itself. History Aach was first mentioned in the year 1100, as part of the Duchy of Swabia. By the year 1150 the settlement was known in Latin as . In 1200, the lords transferred ownershp of the town to the Prince-Bishopric of Constance. Aach was granted town rights in 1283 by King Rudolph I of Germany. For the next centuries it was a part of Further Austria until the House of Habsburg purchased the County of Nellenburg, the county in which Aach was situated. In 1499 battles of the Swabian War took place right before gates of Aach. Only 26 years later, in 1525, the German 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 Kingdom of Württemberg (from 1810 the Grand Duchy of Baden), which joined the German Empire in 1871. After World War II Aach became a part of the new (West) German state of Baden-Württemberg. Following district boundary redrawings in 1973, the city moved from the Stockach district to its current distract, Konstanz. Jewish history The first record of Jews in Aach is dated to 1518, in which the Jews of nearby Geisingen were accused of murdering a Christian child, an incident that can be considered a Blood libel. Every ten years, the local Jews were required to renew their residence permits. Between 1560 and 1570, five Jewish families resided in the town. Jews could host a maximum of five guests. They were required to notify the authorities upon the arrival of a Jewish visitor, and he could not trade with the local townspeople. In 1583, residence rights, now truncated to five-year increments, were renewed for Aach's six Jewish families. Additional restrictions were imposed on the