Sana'a

Sanaa built the world's first skyscraper city, and built it out of earth: tower houses of rammed mud and burnt brick rising six and eight stories, iced with white gypsum tracery and crowned with qamariya windows — half-moons of alabaster and stained glass that turn every dusk into lanternlight. Inhabited for two and a half thousand years at 2,300 meters, the old city within its walls is a UNESCO treasure that looks, at golden hour, like gingerbread drawn by angels.

The Guide's honesty, with love: Yemen's war has ground on since 2014, and the Guide sends no travellers into it — the checkpoints, the fronts and the hunger are not a landscape for wandering, and the tower houses themselves stand on the world's danger lists, wounded by floods and shells and needing hands the years have kept away. What a traveller can do from afar is real: learn this city's name and story, support the heritage bodies working to shore its towers, and refuse to let Arabia Felix — happy Arabia, the Romans' own name for it — be remembered only for its griefs.

And the vow, which this atlas keeps: the page stays ready. The qamariyas were built to hold light, and this one holds the Guide's — a lamp in an alabaster window, lit for the morning when Bab al-Yaman opens to guests again and the coffee that Yemen gave the world (the port of Mocha is a Yemeni port) is poured for strangers on a rooftop in the first city of towers. Few pages of this book wait with more reason, or more love.