Passage: Great was the predicament of Hugh, and he began doubting whether he could win the contest by force. Adalberon, bishop of Laon, whom Charles expelled when he took the city, had sought the protection of Hugh Capet. The bishop made overtures to Arnulf and Charles, to mediate a peace between them and Hugh Capet. Adalberon was received by Charles favorably, but was made to swear oaths that would bring curses upon himself if broken. Adalberon swore to them all, "I will observe my oaths, and if not, may I die the death of Judas." That night the bishop seized Charles and Arnulf in their sleep, and delivered them to Hugh. Charles was imprisoned in Orléans until his death. His sons, born in prison, were released.

Question: Where was Charles held in confinement?
Orléans