The hook
A colossal concrete flying saucer marooned on a Balkan mountaintop, built by the Communist Party in 1981 and left to rot when the regime fell, its mosaics now peeling in the wind.
01Why it's worth it
On a high ridge in central Bulgaria squats one of the strangest buildings in Europe: a saucer-shaped hall on a stem, with a tall tower beside it once topped by giant red stars, raised as a monument to the Bulgarian communist movement. Inside, a ring of mosaics depicted the heroes of socialism. When the regime collapsed it was abandoned, stripped, and left to the weather, and for years urban explorers slipped in through gaps to photograph the decaying grandeur, ice forming under the dome. It has since been sealed for safety, so you can no longer legally enter, but the exterior alone, this hulking retro-futurist ruin against the sky, is worth the drive, and slow conservation efforts are trying to save the mosaics. It is the definitive spomenik, the Yugoslav-era monumental style, at its most surreal.
02How to experience it
Drive up the mountain road in the warm months and walk around the exterior; do not try to break in, as it is closed and unsafe. Read up on the mosaics and the conservation campaign before you go, since the story of its rise and ruin is the point. Combine with the nearby Shipka pass and its memorial.