Visit the Gondar castles

Moorish palace-fortress of Granada.

Renaissance sea fortress at Helsingor — the Elsinore of Shakespeare’s Hamlet.

One of Europe’s largest castle ruins, sprawled across a travertine hill.

16th-century castle, UNESCO-listed.

Renaissance Radziwill palace and park.

The largest ancient castle complex in the world, with St Vitus Cathedral, the Golden Lane cottages and the hourly guard change.

Granite stelae up to 33 metres tall marking the tombs of the Aksumite kings, near the chapel said to hold the Ark of the Covenant.

Ancient Islamic city of 82 mosques, where hyenas are fed by hand at night.