Built in murus dacicus style, the six Dacian Fortresses of the Orăștie Mountains (Romanian: Cetăți dacice din Munții Orăștiei), in Romania, were created in the 1st centuries BC and AD as protection against Roman conquest, and played an important role during the Roman–Dacian wars.

The six fortresses — Sarmizegetusa Regia, Costești-Cetățuie, Costești-Blidaru, Piatra Roșie, Bănița, and Căpâlna — that formed the defensive system of Decebalus were designated as a UNESCO World Heritage Site in 1999.

The town of Sarmizegetusa Regia was the capital and major fortress of the Dacian kingdom, probably built in the mid first century BCE.

It consisted of perimeter walls and fortifications, a sacred precinct, and a settlement area primarily for nobles and supporting servants.

[1] Piatra Roșie, which means Red Rock, was a Dacian hill fort two days march to the west from Costești-Cetățuie, at Luncani in Boșorod commune.