The southern edge of the Petrovský hill is made up of very valuable historical buildings of former canon houses and the present-day bishopric. These houses are baroque new buildings, built on medieval foundations. All of these buildings also have underground spaces with very interesting cellars.
One of the most interesting is the cellar of house No. 7. If we descend through the cellar made of mixed brickwork and rubble stone to the lowest part of the basement, we are in for a real treat. The weathered cracked diabase rock, enriched with natural minerals, has created a perfectly coloured cellar gem. The water dripping in a regular rhythm from the rock vault adds to the uniqueness of this place, which today serves as the wine archive of the bishopric. The fact that the right-hand part of the cellar is almost under the cathedral certainly contributes to this.
The building of the former rectory No. 8, which became the seat of the Bishop of Brno in 1777, was built in the Renaissance style on the remains of a medieval building. However, the origin of the preserved cellars under the garden on the west side of the palace remains unclear. The wide exit from the cellars into the garden confirms the assumption that a building probably stood here. However, neither its perimeter nor its layout can be determined from the surviving underground.
The cellar of house No. 6 is two-storeyed. The lower level of the cellars is below the level of the courtyard and is accessible by a staircase, which leads down to a large cellar space (10 m long, 6 m wide), vaulted with a semicircular vault. The northern face of the cellar is formed by a rock massif into which a smaller space, also in rock, is carved. This Gothic cellar was used in the past to store wine, as evidenced by the remains of a preserved oak barrel grate.