An immense raw concrete dome known as the Buzludzha monument was built between 1974 and 1981 on the Hadzhi Dimitar peak in the Central Balkan massif. Standing at an altitude of 1441 meters, the structure was constructed to celebrate the Bulgarian Communist Party and features 510 square meters of mosaics made with 35 tons of cobalt glass. The monument was inaugurated in 1981 to commemorate the ninetieth anniversary of the founding congress of the Bulgarian Communist Party, then known as the Bulgarian Social-Democratic Workers' Party. Designed by architect Georgi Stoilov, the building was intended to merge Soviet futurism with a near-religious dimension, resembling a secular temple dedicated to the party's ideology. The monument's interior was once equipped with a heating system and sophisticated lighting intended for official ceremonies and mass gatherings. However, the site was abandoned in 1989 following the fall of the communist regime, leading to the degradation of the mosaics due to exposure to weather, water infiltration, and vandalism. The structure has since become a popular destination for urbex enthusiasts—those who explore abandoned places—photographers, and curious visitors, despite an official access ban. In September 2021, the monument was classified as a national heritage site by the Bulgarian National Institute of Immovable Cultural Heritage, allowing for the first time the request of public funds for its preservation. The Bulgarian Ministry of Culture recognized the building as a national cultural value, protecting it from demolition. Restoration projects have begun, focusing on stabilizing the dome mosaic and securing access for visitors. The Kazanlak municipality, the nearest city, has considered purchasing the monument to transform it into a tourist attraction, while the Open Buzludzha project aims to convert it into a multifunctional cultural center under the scientific control of ICOMOS, an international organization that advises on heritage conservation. Despite its deteriorating condition, the Buzludzha monument continues to attract approximately 50,000 visitors annually. Its unique design, historical significance, and the contrast between its grand communist-era vision and its current state of decay have made it a symbol of both Bulgaria’s past and its ongoing efforts to preserve its cultural legacy.