Cathedral of the Assumption of Mary, Chur

The current cathedral building was constructed between 1150 and 1272 as a late Romanesque pillar basilica. The decision to build this structure dates back to the time of Bishop Adalgott (1151–1160). According to the current state of research, construction began from the east and extended over several stages, with the previous building gradually giving way to the new one. After approximately 120 years of construction, the completed cathedral was consecrated on June 19, 1272.
In 1828/1829, following the Hof fire of May 13, 1811, the cathedral received its current tower with a curved dome, which was rebuilt on the foundations of the previous tower, built around 1500.
Like a fortified church, the cathedral, with the Episcopal Palace and the Canons' Courtyards, forms an ecclesiastical precinct on a rocky terrace above the old town of Chur. Archaeological excavations at this site have uncovered traces of a late Roman fort dating back to the 4th century. It is believed that the Romans used the unique location of the rocky outcrop as a seat for the leadership of the province of Raetia.
Source: de.wikipedia.org/wiki/Kathedrale_St._Mari%C3%A4_Himmelfahrt_(Chur)