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Built in the 11th century, beautiful Bab Zuweila was an execution site during Mamluk times, and today is the only remaining southern gate of the medieval city of Al Qahira. There are interesting exhibits about the gate's history, all with thorough explanations in English, inside the gate, while up on the roof you get panoramic vistas that stretch out to the citadel. Those with a head for heights can also wind their way up to the top of the two minarets.
The spirit of a healing saint was (and still is) said to reside behind one towering wooden door, which supplicants have studded with nails and teeth as offerings over the centuries.