Old City of Sana'a

Facades of rammed earth trimmed with white gypsum stack storey upon storey in Sana'a, a mountain city 2,200 metres up that has been lived in for more than two and a half millennia. Early in Islam's history, during the 7th and 8th centuries, it became a springboard for the faith; its old city counts 103 mosques, 14 bath-houses and more than 6,000 houses predating the 11th century. UNESCO inscribed Sana'a in 1986.