Velebit (pennant number P-01) was a modified Una-class midget submarine and the only submarine to see service with the Croatian Navy. It was built for the Yugoslav Navy during the 1980s where it was named Soca. At the outbreak of the Croatian War of Independence Soca was being overhauled in the Brodogradilište specijalnih objekata division of Brodosplit shipyard in Split, Croatia. Although stripped of all equipment, it was preserved from the retreating Yugoslav forces by the shipyard workers.
With modifications that were aimed at improving the ships endurance by including a diesel generator, it was launched as Velebit (P-01) in 1996. A few years later it was out of service because of the need to acquire a new set of batteries, which in turn, never happened. After unsuccessful attempts of selling it to a foreign buyer, it was offered to various museums in Croatia with a final destination still pending.