Pictured: Twelve jaw-dropping projects that will revolutionise Saudi Arabia, from an upside-down skyscraper with a secret entrance to the world’s largest floating structure and a $500bn ‘vertical Manhattan’

Tabuk Province, Saudi Arabia. A barren corner of the country, with little that’s apparent to recommend it as a destination but endless sunlight and abundant salt water.Nevertheless, Mohammed bin Salman, crown prince and de facto leader of the region, saw this...