Felix Romuliana is an ancient Roman archaeological site located in modern-day Serbia. It was built in the late 3rd century AD by the Roman Emperor Galerius as a palace complex and is known for its impressive architecture and beautiful mosaics. The site is recognized for its historical significance and is a UNESCO World Heritage Site. The complex includes several structures, such as temples, residential buildings, and a large courtyard. The ruins showcase the blend of Roman and local architectural styles, reflecting the cultural influences of the time. Today, Felix Romuliana attracts visitors interested in Roman history and archaeology.