Plovdiv reached an agreement that the Principality of Bulgaria and Eastern Rumelia had a common government, Parliament, administration, and army. Today 6 September is celebrated as the Unification Day and the Day of Plovdiv. After the unification, Plovdiv remained the second most populous city in Bulgaria after the capital Sofia. The first railway in the city was built in 1874 connecting it with the Ottoman capital, and in 1888, it was linked with Sofia. In 1892 Plovdiv became host of the First Bulgarian Fair with international participation which was succeeded by the International Fair Plovdiv. After the liberation, the first brewery
History of Plovdiv BC, Plovdiv was conquered by Philip II of Macedon, the father of Alexander the Great, who renamed it "Φιλιππόπολις", "Philippopolis" or "the city of Philip" in his own honour. Later, it was reconquered by the Thracians who called it "Pulpudeva" (from Philipopolis). In 72 BC, Plovdiv was seized by the Roman general Terentius Varo Luculus. The city was incorporated into the Roman Empire, where it was called "Trimontium" ("City of Three Hills") and served as capital of the province of Thrace. Thrimontium was an important crossroad for the Roman Empire and was called "The largest and most beautiful of all