Altenberg Cathedral

The Cistercians began this in 1259 in a wooded valley of the Bergisches Land, and it is called a cathedral only by custom; it was never a bishop's seat. Cistercian rules restricted decoration, so the interior is very plain, with the effect coming from proportion and light rather than ornament. The west window, about a hundred and forty square metres of grisaille glass in mostly grey and white, is among the largest medieval windows in Germany. The abbey was suppressed in 1803, damaged by fire, and restored from 1834. Since 1857 it has been used by Catholic and Protestant congregations together under a royal decree, an arrangement that has held ever since.

What you actually see

• The plain interior - a Gothic church stripped of ornament by Cistercian rule.
• The west window - about 140 square metres of medieval grisaille glass.
• The shared use - Catholic and Protestant congregations since 1857.
• The valley setting - a church alone in wooded ground with few other buildings.

When to go

Year-round; the church closes during services for either congregation. Organ recitals run through summer. The valley is a walking area from Cologne.

Honest expectations

It is one building with little around it beyond a cafe and car park. Services interrupt visits. The plainness disappoints those expecting decoration.

Nearby

Cologne lies southwest; Schloss Burg is east.