While walking around Sibiu, Romania, you’ll start to notice something a bit odd. You may even get the sense that someone—or something—is watching you. While you gaze at the city’s architecture, you’ll start to realize the houses are staring back.

Many of the houses on the south and east sides of the city look as though they have eyes peering from their roofs. These cartoonish features give the impression that the buildings (much like Sibiu’s notorious party crowd) never sleep.

Though the eyes may look like some sort of sinister Big Brother surveillance program, they’re actually just oddly shaped windows. Houses use them as a ventilation system for their attics, which were used to store products needing a dry environment. Most of the “eyes” were built between the 15th and 19th centuries.

Despite their practical purposes, some like to claim these peepers were built to instill fear in people, letting them know they were always being watched and to behave accordingly. When dictator Nicolae Ceauşescu was in power, this architectural detail felt extra disturbing to the citizens. It wasn't enough that phones were being tapped, people were being questioned, and families were blacklisted. It’s as if the houses were watching their every move, too.

And now, though Ceauşescu is long gone, the eyes are still there, as they have been for centuries. Unblinking, unmoving, and always observing.