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 tradition. The name "Plovdiv" first appeared around that time and is derived from the city's Thracian name "Pulpudeva" (assumed to be a translation of Philippopolis, from Pulpu = Philippou and deva = city), which was rendered by the Slavs first as "Pəldin" ("Пълдин") or "Pləvdin". Under the rule of the Ottoman Empire, Plovdiv was a focal point for the Bulgarian national movement. During that period Plovdiv was an economic center along with Constantinople, Odrin and Thessaloniki. Due to trade, the emerging Bulgarian bourgeoisie became significant in the society. Trading with Russia and Europe these people experienced political and cultural influences.