In December, public access was halted; first in order to survey what actually is there, next to develop a strategy for protecting it, and then to open up Mada’in Saleh to the outside world. My advance visit is aimed at providing an amuse-bouche, as it were.

In the bright morning sunlight, Ahmed escorts me through locked gates, past the German-built railway-line linking Damascus with Medina, which Lawrence bombed (“there are still local tribes which call their sons Al-Orans”), to the celebrated Nabatean rock tombs.

Doughty first heard about these in Petra, 300 miles north. Fifty years earlier, an awe-struck British naval commander had gazed in disbelief at Petra’s imperishable Treasury, murmuring, as many continue to do: “There is nothing in the world that resembles it.” He was wrong.

If a little less rosier than her sister city, Mada’in Saleh shares her capacity to stagger. Out of the flat desert, one after another, the ornate facades rise into sight, 111 of them, carved into perpendicular cliffs up to four storeys high, their low doorways decorated by Alexandrian masons in the first century AD, with Greek triangles, Roman pilasters, Persian flowers, Egyptian sphinxes, birds.

“This is a twin to Petra,” Ahmed says. Except that in Petra we would be bobbing among crowds.

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