Sanatório de Valongo
Sanatório de Valongo (officially Sanatório Mont'Alto) is a massive, decaying sanatorium located on the isolated slopes of Serra de Santa Justa near Valongo, Porto. Built in 1958 to treat patients suffering from advanced tuberculosis, the hospital housed up to 350 patients at a time during the height of the epidemic in Portugal. Due to overcrowding, minimal medical cures at the time, and high mortality rates, thousands of individuals died painful deaths within its concrete walls. Abandoned in 1961 after antibiotic breakthroughs rendered sanatoriums obsolete, the decaying ruins became notorious across Europe as one of Portugal's most active and terrifying paranormal locations, plagued by reports of disembodied screams, shadow figures, eerie laughter, and aggressive localized cold spots.