Novi Sad, Serbia

Located on the Danube River, Novi Sad is the second largest city in Serbia and a laid-back alternative to the capital city of Belgrade. The Petrovaradin Citadel towers over the ancient city on a 131-foot (40-meter) slab of volcanic rock. The fortress was originally constructed under Roman rule; however, Charles Eugene de Croy laid the “modern” citadel from 1692 – 1780. It features many underground tunnels that remain intact today. Archaeological investigation has uncovered remains from a Paleolithic settlement on the same site dating from 19,000 to 15,000 BC, as well as Bronze Age relics. Its iconic clock tower features a minute and an hour hand that have been reversed in size, so that fisherman can read the time from far out at sea. Every July, the fortress hosts the “EXIT Music Festival,” the largest music festival in Serbia and one of the largest in Europe.