Cordes-sur-Ciel (French pronunciation: [kɔʁd syʁ sjɛl]; Occitan: Còrdas, [ˈkɔɾðos], before 1993: Cordes)[3] is a commune in the Tarn department, region of Occitania, Southern France.

The fortified town was built in 1222 by Raimond VII, the Count of Toulouse, who, though not a Cathar, tolerated what other Catholics considered heresy.

It was intended to replace the village of Saint-Marcel, which was burnt down by the troops of Simon de Montfort in 1215, during the Northern baron's crusade against the Albigensians.

The citizens of Cordes, having built their homes within the original 13th-century ramparts, later escaped heavy damage during the religious wars at the end of the 16th century.

Though the name was just "Cordes" at the time, Ramel-Cals liked to call it "Cordes-sur-Ciel" to reflect the town's site on a hill above the clouds that frequently collect in the river valley.