Pula Arena is located in the city of Pula and is one of the best places to visit in Croatia. The Pula Arena is an amphitheater that was built by the Romans and is one of the most preserved Roman amphitheaters of today. The Pula Arena still has all four side towers in place. While going inside the amphitheater will cost you an entrance free, even exploring the arena from the outside will leave you in awe.