The Plovdiv Regional History Museum consists of four expositions housed in different building in the central area of the city. The “Unification of Bulgaria” exposition is on display inside the museum’s main administrative building on Unification Square and is dedicated to the history of the region of Plovdiv from 1878 to 1885, during which time the country was split into two halves – Southern Rumelia, which remained an autonomous province Ottoman province with Plovdiv as its capital, and the Principality of Bulgaria. The museum building originally served as the seat of the Eastern Rumelian Regional Assembly, and still retains its authentic 19th century architecture to this day. It has 5 exposition halls which contain personal belongings, stamps, weaponry, photographs and documents related to the participants in the Unification and the Serbo-Bulgarian war.