Begin your tour in front of the double gates at the entrance to Zerostrasse. Beneath Pula, discover an entire underground world made up of tunnels that stretch through almost the entire city, today known as Zerostrasse. The Pula underground tunnels were created during World War I as a shelter in case of air raids on the city.

The underground tunnel system consisted of shelters, trenches, galleries, and passages, as well as ammunition depots and communication corridors.

The Kaštel, which served as a barracks and observation post during the Austro-Hungarian Monarchy, as well as a warehouse and prison for prisoners, hides two tunnel shelters under its slopes. One is located at the foot of the fortress itself, while the other is located at the foot of the hill (Zerostrasse). It is about 400 metres long and was primarily used to connect the city centre.
In its centre is a unique space that is led to and meets underground tunnels whose entrances are located on four different sides at the foot of the Kaštel. Carefully planned entrances to the system allow for proper air circulation, the temperature of which is between 14 and 18 °C throughout the year. The corridors are 3 to 6 metres wide and 2.5 metres high.

From the Zerostrasse tunnel, take an lift to the Kaštela fortress. The Pula Kaštela fortress rises on the central hill above the old city centre and is one of the most recognisable symbols of the city. It is located at an altitude of about 34 metres above sea level, so its silhouette dominates the panorama of Pula.

Today, this Baroque fortress from the 17th century houses the Historical and Maritime Museum of Istria, which tells the storey of the region through interesting exhibitions - from prehistoric times and the Roman period, through the Middle Ages and Venetian rule, all the way to modern times. The ramparts and lookouts offer impressive views of the Arena, the harbour, shipyard cranes, and the sea of red roofs that cover the city.

For visitors, Pula's Kaštel fortress offers an excellent combination of museum history and outdoor walks. Walk through stone courtyards, slowly climb to the ramparts, and along the way see exhibitions that depict everyday life, seafaring, and the numerous governments that have shaped Istria over the centuries.

Pula's Kaštel fortress stands on a hill that has been important for more than two thousand years. Long before the present-day fortress was built, a prehistoric Histrian hillfort was located here, and later a Roman military camp and acropolis. Over the centuries, the site developed into a medieval fortress, and finally into the star-shaped Venetian fortress of today. There are few locations in Pula where you can experience so many historical layers in one, compact space.

During a visit to the Pula Kaštel fortress, stroll through the central courtyard, climb the bastions, and enjoy sweeping views of Pula, the Arena, and the Adriatic Sea.