Bulgaria’s State Opera in Stara Zagora is celebrating its 100th anniversary with an open-air premiere of Tsar Kaloyan, a landmark work by renowned composer Pancho Vladigerov.

Performances will take place on 17 and 18 July at 9 p.m. at the Ancient Forum “Augusta Traiana”, the organisers announced.

Vladigerov's opera, with a libretto by poet and symbolist Nikolay Liliev and based on Fanny Popova-Mutafova’s play The Tower of Baldwin, holds special significance for the company. The Stara Zagora Opera marked its 50th anniversary in 1975 with a performance of the same work, which was attended by the composer himself, Bulgarian National Radio’s Hristo Botev programme recalled.

“Pancho Vladigerov was one of the most educated composers of his time. He introduced a musical language that was difficult for the early 20th century and remains challenging today,” said Ivaylo Krinchev, principal conductor of the State Opera in Stara Zagora, who will lead the performances.

Tsar Kaloyan will also be staged later this month at the historic Tsarevets Fortress in Veliko Tarnovo on 25 July.