Basilica of SS. Peter and Alexander

The origins of the collegiate church date back to the mid-10th century, when Duke Liudolf of Swabia and his wife Ida initiated its construction. Their son Otto, also Duke of Swabia, founded the Collegiate Chapter of St. Peter and Alexander, along with a chapter school, around 974. Construction of the collegiate church began in 975. With the donation of Aschaffenburg to Electoral Mainz in 982 through Duke Otto's legacy, the chapter came under the patronage of the Archbishops of Mainz. The significance of the collegiate church grew with Aschaffenburg's development into the secondary seat of the Archbishops of Mainz. The chapter quickly gained economic power, becoming the city's largest landowner, possessing numerous parishes, estates, and mills. At its peak, it housed up to 28 canons. In 1802, the collegiate chapter was dissolved during secularization. Since 1958, the church has held the title of a Basilica minor.

The Cathedral of St. Peter and Alexander is located in the city of Aschaffenburg, in the state of Bavaria, Germany. It is situated on a hill, overlooking the city center.

The former collegiate church now serves as a Catholic parish church. Since 1861, the chapter house has housed the Collegiate Museum, which displays some of the church's art treasures. The complex is a protected architectural monument in Bavaria.

• Palais Salm (residence, approx. 105 m away)
• Schönborner Hof (residence, approx. 110 m away)
• House of the Barons of Reigersberg (residence, approx. 192 m away)
• Noble seat Echterhaus (residence, approx. 290 m away)