Zerostrasse: Explore the Secret Tunnels Beneath Pula

Zerostrasse is a network of Austro-Hungarian underground tunnels beneath Kaštel hill in the centre of Pula, Croatia, built during the First World War as air-raid shelters. About 400 m of corridors are open to visitors, entered at Carrarina 3 near the Twin Gates. A lift connects the tunnels to Kaštel fortress and the Historical and Maritime Museum of Istria. Open daily: 9:00 - 21:00 from 1 May to 30 September, 9:00 - 17:00 from 1 October to 30 April.

Roman monuments may dominate Pula above ground, but another part of the city’s history lies hidden beneath its streets.

Zerostrasse at a glance

Why were the tunnels built?

Before and during the First World War, Pula was the principal naval port of the Austro-Hungarian Monarchy, so protecting the city, its inhabitants and its military infrastructure was a priority. Authorities dug tunnels and shelters under the central hills as protection from air raids. The system included communication passages, storage areas and munitions depots.

The accessible tunnels beneath Kaštel have four entrances around the base of the hill. They converge in a central underground chamber, and the layout lets air circulate through the system.

A city beneath the city

The underground system continued to develop after the First World War. New fallout shelters were built after the Second World War, and the tunnels again served as shelters during the Croatian War of Independence. Today Pula’s shelters can together hold more than 50,000 people, nearly the city’s whole population.

Rock and concrete walls, subdued lighting and the echo of footsteps create an atmosphere far from the lively streets above. The tunnels stay cool all year and never get warmer than about 20 °C, which makes them a welcome escape in summer. A light jacket is still a good idea, even in August.

From the tunnels to Kaštel

A lift connects the lower tunnels with the underground level of Kaštel, home to the Historical and Maritime Museum of Istria. From there you can continue to the fortress and enjoy panoramic views over Pula. A single ticket covers Zerostrasse and Kaštel.

One visit takes you through several periods: Roman streets outside, Austro-Hungarian tunnels below and a hilltop fortress above.

Planning your visit

The main entrance is at Carrarina 3, close to Pula’s Twin Gates. Opening hours differ between summer and winter, so check ppmi.hr before you go. Wear comfortable shoes, and expect subdued lighting and cool temperatures.

Suggested route: start at the Amphitheatre, walk through the old town to the Twin Gates, descend into Zerostrasse and take the lift to Kaštel.

Stay close to Pula

• Grand Hotel Brioni Pula: 10 min from the old town.
• Park Plaza Histria Pula: 10 min from the old town.
• Park Plaza Arena: 10 min from the old town.
• Park Plaza Verudela: 10 min from the old town.
• Arena Verudela Beach: 10 min from the old town.

Frequently asked questions

What is Zerostrasse in Pula?

A network of Austro-Hungarian WWI tunnels beneath Kaštel hill, now a museum site open to visitors.

What are the opening hours?

9:00 - 21:00 from 1 May to 30 September and 9:00 - 17:00 from 1 October to 30 April.

How much are tickets?

Adults 8 €, children 5 - 16 years 3 €; a combined ticket includes Kaštel.

How long does a visit take?

30 - 60 minutes for the tunnels, and more if you add Kaštel and the museum.

Is Zerostrasse good on a hot or rainy day?

Yes, it is cool and indoors, with temperatures never above about 20 °C.

Is it accessible?

The tunnels and entrance are wheelchair accessible.

Where is the entrance?

Carrarina 3, near the Twin Gates in the centre of Pula.