Crypt of Sant'Eusebio - Credit: Wikimedia Commons
The church of Sant'Eusebio was a church of Pavia, of which today only the crypt remains. The church was probably built by the Lombard king Rothari (636-652) as the city's Arian cathedral. It later became the fulcrum of the conversion to Catholicism of the Lombards initiated by Theodolinda and the monks of San Colombano and which later received, precisely in Pavia, a great impulse from King Aripert I (653-661) and from Bishop Anastasius. Read more on Wikipedia
Source: en.wikipedia.org