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
PFC Lokomotiv Plovdiv Another merger follows in 1945 with the "Catholic" club "Parchevich". After this wave of mergers, like many others in the country, the club is renamed to an abbreviation of the biggest clubs merged - the new name is "S.P.-45", meaning "Sportclub Parchevich - 1945". However, because of the "Western" phrasing ("sport" and "club" are non-Slavic words) the team is renamed again before the start of the season - the name of the club becomes ""Slavia" Plovdiv". In 1947 a new wave of consolidations of the sport organisations in the country sees Slavia Plovdiv merge with the team of the cooperative