St. John's Church

Mainz, Germany

St. John's Church is located beneath Mainz Cathedral. This 1100-year-old church was the first episcopal see of the Bishop of Mainz. It is the oldest church in Mainz, the oldest cathedral in the Germany of today and the only preserved cathedral building from late Carolingian and early Ottonian time in Germany.

St. John's Church is predominantly Carolingian in style, but later exterior additions over many centuries have resulted in the appearance of various architectural influences seen today. It comprises three naves and stands under the patronage of John the Baptist today. It can be assumed that the church was dedicated initially to Martin of Tours since Martin is the Patron saint of the Roman Catholic Diocese of Mainz, then to St. Salvator, consecrated in 911 by Archbishop Hatto I and served as the cathedral for the Bishop of Mainz until the appointment of Willigis as Archbishop of Mainz in 975. It is documented that archbishop Erkanbald was buried in this first cathedral.

The church building dates from the early medieval era; construction of the main area of the church began in the 7th century. The successional building kept the guidelines of the floor plan of the original building. Knöchlein speculates that as the predecessors have also been made of stone, which is uncommon for the post-Roman period, leads to the conclusion that the early Christians in Mainz worshipped first in either a civilian building near the Forum or on the foundations of an ancient temple.

Archbishop Hatto's church is one of the few remaining late Carolingian churches. It was built as a basilica, its wide central nave is higher than the narrow aisles. The building was designed as a double chancel facility in east-west direction. Hatto has partially used wall remains of the first building. There are remains that have been integrated into the new church. In other places, this was completely demolished. The archeologists assume that it was a planned demolition and reconstruction - probably a smooth transition. The present floor level is probably the seventh level in total.

In the East the choir room is as wide as the nave. The side walls of the east choir are opened by two arched windows and overlying round windows (so-called Oeil-de-boeuf). West to the choir joins a rectangular nave flanked by narrow aisles. The walls of the nave are at the top of the clerestory broken by four arched windows, including four arcades open each (now closed) in the former aisles (now parish rooms).



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Bischofsplatz 10, Mainz, Germany
See all sites in Mainz


Founded: 10th century AD
Category: Religious sites in Germany
Historical period: East Francia (Germany)

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User Reviews

Uwe Furchheim (8 months ago)
Not only a beautiful church, but also very exciting excavations in the church! And you could get all questions about details answered by the very knowledgeable "watchdog" (as well as interesting tips on excavation results that you would otherwise easily have overlooked). Admission is free, but donations to support the infinitely expensive restoration are of course welcome.
Taurus C. (10 months ago)
Unfortunately still a construction site at the moment, but the interior of the church and the excavations are still well worth seeing. Very interesting which epochs were all uncovered. Information boards everywhere. Nice that access to this "construction site" is made possible. Recommended
EssSea Jee (13 months ago)
The "old cathedral" is the oldest church in Mainz and the second oldest preserved bishop's church in Germany. Extensive historical material dating back to Roman times was discovered during floor work. Archbishop Erkanbald's sarcophagus can also be seen. The excavation site can be visited on church open days. If you let that sink in, you can feel the long history of the city.
Erik Swiatloch (2 years ago)
Damn exciting church that can't really be used as a "church" at the moment. During construction work a few years ago, some very old foundations were found; since then the church has been an excavation site. However, you can visit them and learn more about the found objects from the information boards. The highlight is an approximately 1000 year old coffin which is still being explored in the middle of the church.
Marco della Peruta (3 years ago)
The cathedral is under reconstruction. There were ruins discovered which shows it as a place of worship through many ages.
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