Labyrinth under Vegetable Market, Brno, Medieval underground passages in Brno, Czech Republic

The Labyrinth under the Vegetable Market is a system of corridors and cellars beneath Zelný trh, 6 to 8 metres below the surface. Most of the vaults date from the Baroque era, though they were founded in the Middle Ages; the largest cellar is nearly 23 metres long and 3.5 to 4 metres high, and the deepest lies 13 metres down.

Merchants built these passages in medieval times to store food, wine, and beer in cool conditions, which became essential for a growing city. This underground storage system was crucial to Brno's development as a trading hub.

The cellars served for food storage, beer brewing and maturing wine in barrels, and as shelter in wartime. The market above has run since 1190 and kept its name Zelný trh for 700 years, continuing even under communism when private trade was outlawed.

The cellars lie 6 to 8 metres below Zelný trh, and the deepest reaches 13 metres; the largest cellar is about 23 metres long with a height of 3.5 to 4 metres. The cellars were only fully connected during the 2009 reconstruction and opened to the public in 2011.

Among the displays are replicas of medieval punishment equipment that reveal how justice was administered publicly in the medieval city. These objects serve as a stark reminder that the market square above was not only a place of commerce but also of public discipline.