The interior is even more amazing
History Ruins
What is a ruin? We’re running off of “You know it when you see it” at the moment. Ruins should be non-functioning structures of some age, or their function reduced to tourism and the like.
Generally speaking, specific items from a ruin should go to !historyartifacts@lemmy.world
Illustrations of ruins (or their reconstructions) should go to !historyillustrations@lemmy.world
Photos of ruins back when they were functioning should go to !HistoryPorn@lemmy.world
It commemorated the events of 1891, when a group of socialists led by Dimitar Blagoev assembled secretly in the area to form an organized socialist movement that led to the founding of the Bulgarian Social Democratic Party, a forerunner of the Bulgarian Communist Party (itself a forerunner of the current Bulgarian Socialist Party).
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The monument exemplifies the futurist architecture common to many state-constructed communist buildings. All maintenance ended with the fall of communism in 1989, and the building remains closed to the public due to the hazards of the weakened structure.[1] The Buzludzha Project has helped to begin work on the monument's preservation, with the eventual aim of creating an interpretation center for Bulgarian history.[2]
https://en.wikipedia.org/wiki/Buzludzha_monument
More pictures on that wikipedia page, very interesting. The site of the Battle of Shikpa Pass (from the Russo-Turkish War) is just a couple miles away too.
We got one of those in Rockwall, TX, USA. It's a little bit smaller, made of steel, and has some spray paint on it now, but looks about the same.