The chapels will be opened on St John's Day, and service will be held by Apostolic Nuncio Petar Rajic.

"It's a wonderful day when we will open up more of the Cathedral's treasures. The three chapels, closed since the return of the Cathedral, will now start a new life," Vilnius Archbishop Gintaras Grusas said.

Nationalized valuables, currently held in the museum, will also be returned to Vilnius Cathedral.

People willing to visit the new chapels accompanied by a guide will be able to book paid excursions with the Church Heritage Museum.