Soviet ruins - Buzludzha Monument

After looking through some more pictures of places I decided I'd like to go with a kind of soviet ruins theme, because their designs look somewhat intimidating yet ornate. I found The Buzludzha Monument that sits on a historical peak in the Balkan Mountains, Bulgaria, to be an interesting building that could be modeled to explore from the inside and outside.

History:
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 The Monument was opened in 1981.^[2] No longer maintained by the Bulgarian government, it has fallen into disuse.

-just a brief rundown from wikipedia

here are some picture examples of the exterior
before abandonment:

After abandonment:

Also the interior..
Before abandonment:

After abandonment: