St. Gereon's Basilica

St. Gereon in Cologne is one of the city's twelve great Romanesque churches and one of its most unusual: a basilica with a ten-sided domed hall that grew out of a late Roman oval building. If you have already seen the cathedral and want to explore more of Cologne's medieval and ancient layers, this quiet church in the Altstadt-Nord district is a rewarding stop, with a crypt, a medieval floor mosaic and a striking interior.

A short history

The core of the church is an oval structure from the second half of the 4th century, built on a Roman burial ground outside the old city. Its original purpose is still unknown. The church became a collegiate foundation in 839, and over the centuries it was extended with a long choir and crypt.

The best-known chapter came between 1219 and 1227, when the ancient oval was enclosed and raised into the ten-sided domed hall called the Dekagon. The dome rises about 34.55 meters (113 feet). The baptistery followed in 1242 to 1245. Pope Benedict XV raised the church to a minor basilica in 1920. Heavy bomb damage in World War II hit the Dekagon in particular, and services have been held there again since 1984.

A medieval legend says St. Gereon and fellow soldiers of the Theban Legion are buried here. Historians find no evidence for it, but it made the site a place of pilgrimage for centuries.

What to see

• The Dekagon: look up into the ribbed dome.
• The crypt, with a Staufer-era floor mosaic showing scenes from the Old Testament around Samson and David.
• The baptistery, with 13th-century murals.
• The exterior apse with its two flanking towers.

Allow 30 to 60 minutes. This is a working parish church, so be quiet and considerate during services.

Opening hours and admission

As of October 2026, the parish lists the nave as open Monday to Saturday from 10 a.m. to 6 p.m. On Sundays outside services the church is usually closed, because opening is run by volunteers. The porch is open daily from 10 a.m. to 6 p.m. The parish does not list an admission fee for visiting the church. Guided tours are organized by the parish; the contact is the parish office at +49 221 2924 0565. In November the 25th edition of the Orgelfesttage organ concerts begins in the candlelit Dekagon.

How to get there

St. Gereon is at Gereonskloster 2, west of the cathedral, within walking distance of Cologne Central Station (Hauptbahnhof). Cologne is easy to reach by Deutsche Bahn from Düsseldorf, Frankfurt and other cities, and the Deutschlandticket is valid on local public transport. The parish does not mention parking, so public transport is the easier option.

Is it worth visiting?

Yes, if you like Romanesque architecture, medieval history or simply a quieter alternative to the cathedral. Information about accessibility and access to the crypt is not published by the parish, so contact the office in advance if you need step-free access.

Nearby

Cologne Cathedral and the Kolumba art museum are both within walking distance.