Plovdiv is the second-largest city in Bulgaria, after Sofia, with a population of 341,873(http://www.nrnm.nsi.bg/index.php?ezik=en&f=8&s=1&date=28.11.2006&e=1&s1=4&c1=1&a1=340000&c=1&s2=5&c2=1&a2=100000). It is the administrative centre of Plovdiv Province in southern Bulgaria, as well as the largest and most important city of the historical region of Thrace, famous for its ancient and diverse culture and millennial history.