The Franciscan monastery of St. Bernard was founded in 1451 by the Italian Franciscan monk and passionate preacher Jan Kapistrán (John of Capistrano) during his second stay in Brno. The site for the monastery was purchased beyond the city walls in the south below Puhlík, near the mill channel. At the time of the first Swedish siege in 1643, the commander of Brno, Colonel Schönkirch, set fire to the Franciscan monastery for strategic reasons, and it burned down with the Church of St Bernard. The Franciscans relocated to the town centre and were given the church of St Mary Magdalene and four Gothic buildings in exchange for the destroyed property. The monastery was completed there in 1654.

Under the eastern wing of the monastery and partly under the two-storey street building as well as below the square, there are extensive cellars of several levels and intricate layouts. Only parts of quarry stone masonry have been preserved from the former Romanesque building. Gothic masonry was also removed from the upper part, apparently during the construction of the monastery, and replaced by baroque walls with vaults. The full extent of the historic underground has not yet been explored.

In September 1982, the vault in the connecting corridors below the square was broken. During garbage collection, the pavement under the truck collapsed through the vault, and the tiles fell through two floors of underground corridors. The accident was repaired under time pressure by covering these spaces in concrete. The extensive cellars under the monastery building were rebuilt in the 1980s and partially structurally secured in a haphazard way. Today, the underground and the entire building are in very poor condition and only timely repair and appropriate use will save these very attractive historic sites in the once popular and romantic Římského náměstí (Roman Square).