A ring of stone walls encircling the town was built between 1530 and 1535 by Bernard of Zvole (lord from 1518 to 1536). Until then, Hlučín had been protected only by earth ramparts and a wooden palisade. The construction of a masonry defence system thus came relatively late, but was all the swifter for it. Within just five years, a stone wall 4.5 metres high and about 2 metres thick was erected, reinforced by twelve semicircular bastions and running for roughly 900 metres in total. The quarry stone was laid in lime mortar, and the loopholes of the bastions were carved from single blocks of stone. The gates at the ends of Opavská Street and Ostravská Street were guarded by square towers twelve metres high. Installed above the passage of the Opavská Gate was the heraldic plaque of Bernard of Zvole, which has survived to this day and is now displayed in the entrance of the town hall.
The defensive system began to fall into disrepair towards the end of the eighteenth century. Around 1770, the roof structure of the Ostravská Gate collapsed and both towers were subsequently reduced in height. In 1821, the wall near the fire station (now the Florian Guest House) was dismantled to make way for a third gate, the Ratibořská Gate, relieving traffic congestion in Ostravská Street. When, in 1829, part of the wall near the Opavská Gate in Na Valech Street collapsed as a result of undermining, a decision was finally taken to demolish the fortifications. The dismantled stone was sold and reused in the construction of the school in Píšť, while smaller pieces were used to level the surface of the square.
The course of the walls can still be traced today in the double ring of streets (Pode Zdí and Na Valech, or Hrnčířská), in surviving stretches of masonry, and in the remains of seven bastions: at Pode Zdí 3a (insensitively plastered in the 1990s), 7 (the western corner of the house), and 15; in the freestanding remnants in Na Valech Street; by the house at 5 Generála Svobody Street; at the edge of the car park in U Bašty Street; and in the garden of 34 Hrnčířská Street. In 1974, a bold plan by Jiří Horák, an architect from Opava, proposed encircling the town walls with a green belt, restoring the bastions, and in some cases even topping them with stylised roofs, while demolishing the residential buildings standing within the zone. The project, however, was never carried out.
