Laufenburg is a municipality in the Swiss canton of Aargau. It is the seat of the district of the same name. On 1 January 2010 the municipality Sulz merged into Laufenburg. It has approximately 2000 inhabitants. On the other side of the Rhine River lies Laufenburg (Baden), Germany. The same name is not by accident, as the two used to be the same city. In the early 19th century Napoleon divided the city. Two bridges now link both cities. In 1985, Laufenburg received the Wakker Prize for the development and preservation of its architectural heritage. History A high point along the Rhine river with a rapids section about from Säckingen Abbey was chosen as a place for a strategic bridge over the river. The Kastvogtei (a feudal land holder appointed by the Abbey) transferred his loyalty to the Habsburgs in 1173. Laufenburg is first mentioned in 1207 as Loufenberc. In this 1207 document, the rights of the Abbey to parts of the village were secured while the castles on both sides of the Rhine were given over to the Kastvogt. This allowed Rudolf II of Habsburg to expand the site to the city. He is considered the founder of the city. After his death in 1232, the family split into the dominant line of Habsburg-Austria and the younger line of Habsburg-Laufenburg. The last representative of the Habsburg-Laufenburg line, Hans IV (1408) sold control of Laupenburg to Leopold III in 1386. It became part of the Further Austria and one of the four Habsburg Forest Cities on the Rhine. During the schism at the Council of Constance in 1415 the Antipope John XXIII fled to Laufenburg and withdrew his resignation. After the Swiss conquest of the nearby Aargau, which was triggered by the schism, Laufenburg was the starting point of several campaigns against the Confederates. In retaliation, Bern, Solothurn and Basel besieged Laufenburg during the Old Zurich War in 1443. During the 15th Century, it was offered as collateral for a loan from Burgundy. As a result, it was briefly under Burgundy's control. During the Thirty Years War it was occupied for 13 years. In 1792 it was the base for the French Revolutionary Army. With the Lunéville peace of 1801 part of the Fricktal went to France and the rest went to the Helvetic Republic in 1802. The Rhine River was chosen as the border between the districts. The complicated