Cetăţile Păgânilor (Pagan Citadels, Hungarian: Bálványos) is a spa in Covasna County, in the east of Transylvania, central Romania. it lies at an altitude of almost 800 metres on the southern slopes of the Bodoc Mountains, some 67 kilometres from Sfântu Gheorghe. The spa is located close to the ruins of the 13th century Cetăţile Păgânilor citadel (Pagan Citadels ; Balvanyos).
The spa is one of several hydrothermal and volcanic features of the region. It lies 10 kilometres from the Santa Ana Volcanic Lake, which is unique in this part of Europe. A geological feature locally known as "The Birds' Cemetery" - precipice with sulphurated hydrogen emanation - is also located nearby.
The spa has been known for its health properties for centuries, but has only been commercially exploited as a spa since the building of a nearby hotel in 1938.