The celebrations on the occasion of the 139th anniversary of the Unification of the Principality of Bulgaria and Eastern Rumelia and the Feast of Plovdiv began with a solemn service at the Church of the Holy Mother of God in Plovdiv, conducted by Metropolitan Nikolay of Plovdiv. 

This was followed by a wreath-laying and a flower-laying ceremony at the memorial plaque for Major Raycho Nikolov, the monument to Gavril Krastevich and the monument to Zahari Stoyanov.

The 48th Memorial Marathon "Unification" also starts in Plovdiv. It crosses several villages and ends on Saedinenie (Unification) Square in Plovdiv. A marathon for kindergarten children and students of all grades has also begun.

The celebrations will continue with a musical program at 6:00 PM. Merry Boys Band will perform at Stefan Stambolov Square. An hour later, at Roman Stadium Square, the "Rodolyubie" Committee will present a reenactment of the events of September 6, 1885. The exhibition "Sandro – Prince Alexander von Battenberg" will be unveiled at the Plovdiv Regional Historical Museum.
The official ceremony marking the historic event will start at 8.30 pm on Unification Square. President Rumen Radev will receive the rank of honor and deliver a speech. Caretaker Prime Minister Dimitar Glavchev will also be among the guests. The celebrations will end with a fireworks show.

The Unification Day is being celebrated across the country with numerous events. In Sofia, a ceremony was held at the Battenberg Mausoleum with the participation of the National Guard. Sofia Mayor Vasil Terziev and Bulgarian Archives State Agency Director Mihail Gruev delivered speeches.

''This day comes to remind us of the lessons of history. In the name of the national cause, politicians must set aside their differences and unite, following their people", said Vasil Terziev. Mihail Gruev emphasized that the Unification is the only cause, aside from Independence, that succeeded without and despite the Great Powers.