The first palisade fortress was built in 1545 on the left bank of the River Nitra as part of the defensive line against the Turks. The second fortress, built between 1573 and 1580, was one of the most important Renaissance fortresses in Europe, based on the architectural plan of the Italian brothers Giulio and Ottavio Baldigara. Its ground plan was a regular hexagon with a regular perpendicular street grid and a central rectangular space inside. It had six bastions: Forgách, Česká, Ernő, Császár, Frigyes and Zserotin. The Turks seized the fortress in 1663 and ruled it until 1685; its recapture was celebrated with great importance across Europe, and bells tolled across the continent at the Pope’s order.
The Nové Zámky fortress was demolished in 1724, but its ground plan can still be found in the town’s coat of arms.
Significant events connected with the town’s history are recorded on bronze plaques laid out in chronological order along the pavement of the pedestrian street leading to the main square.