People look at buildings displaying a light show on the eve of the 100th anniversary of the Chinese Communist Party in Beijing on June 30, 2021. (Photo by Noel Celis/AFP Photo)

School students attend a pioneer induction ceremony in Moscow's Red Square in Moscow, Russia on May 22, 2022. Pro-Communist Russians are trying to preserve the Young Pioneers, which used to be the Communist league for pre-teens in the Soviet Union. (Photo by Sergei Karpukhin/TASS)

A portrait of late communist leader Mao Zedong is seen behind two hostesses as they pose for a picture at the Tiananmen Square during the 3nd plenary session of the National People's Congress in Beijing on March 13, 2016. China's Communist-controlled parliament opened its annual session on March 5 and is expected to appove a new five-year plan to tackle slowing growth in the world's second-largest economy. (Photo by Wang Zhao/AFP Photo)

Girls in red neckerchiefs dance on Red Square, with the GUM, the State Department Store and the Historical Museum in the background, during a ceremony to celebrate joining the Pioneers organization and 100th anniversary of the All-Union Pioneer Organization, in Moscow, Russia, Sunday, May 22, 2022. Pro-Communist Russians are trying to preserve the Young Pioneers, which used to be the Communist league for pre-teens in the Soviet Union. (Photo by AP Photo/Stringer)

A honor guard soldier stands at attention during a memorial religious service for those killed in the 1989 anti-communist uprising in University Square, in Bucharest, Romania, Wednesday, December 21, 2022. Participants and relatives of those killed marked the 33rd anniversary of the anti-communist uprising which started in Bucharest on Dec. 21, 1989 and left more than one thousand people dead and ended the rule of dictator Nicolae Ceausescu. (Photo by Andreea Alexandru/AP Photo)

Communist supporters hold portraits of Soviet leader Josef Stalin as they queue to lay flowers at the grave of Stalin to mark the 139th anniversary of his birth, in Moscow's Red Square, Russia, Friday, December 21, 2018. (Photo by Pavel Golovkin/AP Photo)

Buzludzha is a historical peak in the Central Stara Planina, Bulgaria and is 1441 metres high. In 1868 it was the place of the final battle between Bulgarian rebels led by Hadji Dimitar and Stefan Karadzha and the Ottoman Empire. The Buzludzha Monument on the peak was built by the Bulgarian communist regime to commemorate the events in 1891 when the socialists led by Dimitar Blagoev assembled secretly in the area to form an organised socialist movement with the founding of the Bulgarian Social Democratic Party, a fore-runner of the Bulgarian Communist Party. The Monument was opened in 1981. No longer maintained by the Bulgarian government, it has fallen into disuse. Buzludzha is reached by a 12 km side road from the Shipka Pass.

A general view shows the wreckage of armed trucks on the streets of Budapest at the time of the uprising against the Soviet-supported Hungarian communist regime in 1956. The picture was taken in the period between October 23 and November 4, 1956. (Photo by Laszlo Almasi/Reuters)