Halberstadt Cathedral

Halberstadt cathedral holds one of the most complete medieval church treasuries in the world, with over six hundred objects still in the building they were made for, including tapestries of the twelfth century, liturgical vessels, vestments and reliquaries; most such collections were dispersed or melted at the Reformation or later, and this one survived largely intact. In the ruined church of St Burchardi, a performance of John Cage's Organ2/ASLSP began in 2001 and is scheduled to run for six hundred and thirty-nine years, with notes held for months or years at a time and changes drawing audiences; the next chord changes are published years in advance.

What you actually see

• The treasury - over six hundred medieval objects kept in place.
• The twelfth-century tapestries - among the oldest surviving in Europe.
• The 639-year performance - a Cage organ piece running since 2001.
• The cathedral - a Gothic building on French models with cloisters.

When to go

April to October; the treasury closes Mondays. The organ piece changes note on published dates, which draw crowds; between them it is a single sustained sound.

Honest expectations

Between chord changes there is only one continuous note, which visitors find either profound or absurd. The treasury has limited hours. The town was heavily bombed.

Nearby

Quedlinburg lies south; Magdeburg is northeast.