Halberstadt Cathedral, Gothic cathedral in Halberstadt, Germany.

Halberstadt Cathedral is a Gothic house of worship in the old town of Halberstadt, Saxony-Anhalt. The building shows French Gothic design, a 27-meter (88 feet) tall central nave, and nearly 290 glass windows set into its walls.

Emperor Charlemagne founded the episcopal seat here in 804 at this location in Saxony-Anhalt. The current Gothic building rose between 1236 and 1491, taking the place of an earlier Romanesque structure from the early Middle Ages.

Bishop Konrad von Krosigk brought many of the treasury's Byzantine pieces to Halberstadt in 1205, after taking part in the Fourth Crusade's sack of Constantinople. The collection spans the 5th to the 18th century and includes a large textiles holdings. The cathedral's own medieval furnishings and the treasury together form the largest surviving ensemble of its kind still kept where it was used outside the Vatican.

Guided tours cover the architecture and the treasury collection, while car and coach parking is available near the old town. Interior walkways are level and easy to navigate.

The organ installed in the cathedral in 1361 is thought to have had the first modern chromatic keyboard. The 639 years since that installation became the duration of John Cage's "As Slow as Possible", begun in 2001 not in the cathedral but at the St. Burchardi church, with an end date of 2640.