The Rijeka Tunnel — known locally as TunelRi — is a 350-metre underground passage built by the Italian Royal Army between 1939 and 1942 as a civilian air-raid shelter. During the Second World War it sheltered thousands of residents from Allied bombing raids. After decades of closure it was opened to the public and now serves as a cultural venue and exhibition space.
Walking through the tunnel is a visceral experience. The original construction is largely intact — bare concrete, ventilation shafts, emergency exits cut into the hillside — and the atmosphere is genuinely eerie. Temporary exhibitions on local history and contemporary art are held inside. Entry is free and the tunnel is open daily.