A nice UNESCO cover from Serbia, depicting a complete set issued in 2007 celebrating "Gamzigrad-Romuliana, Palace of Galerius".
Gamzigrad is an archaeological site, spa resort and UNESCO World Heritage Site of Serbia, located south of the Danube river, in the city of Zaječar. It is the location of the ancient Roman complex of palaces and temples Felix Romuliana, built by Emperor Galerius in Dacia Ripensis. The Late Roman fortified palace compound and memorial complex was commissioned by Emperor Caius Valerius Galerius Maximianus in the late 3rd and early 4th centuries. It was known as Felix Romuliana, named after the emperor’s mother. The site consists of fortifications, the palace in the north-western part of the complex, basilicas, temples, hot baths, memorial complex, and a tetrapylon. The group of buildings is also unique in its intertwining of ceremonial and memorial functions. It was declared a World Heritage Site by UNESCO in 2007.
