For its time, Shibam's "Manhattan of the desert" distinction—coined by British explorer Freya Stark in the 1930s—wasn't that far off. According to National Geographic, the city was once an important stop for caravans traversing the spice and incense route along the southern Arabian plateau. 

Shibam's city planning was also before its time. The somt seven-story high buildings were built on a rectangular grid plan of streets and squares. They were strategically built on a rocky spur above a giant wadi —a river bed that remains dry except in the rainy season—positioned high enough to see enemies approaching. As UNESCO elaborates, Shibam and its location in the heart of Yemen's Wadi Hadramaut "constitute an outstanding example of human settlement, land use and city planning."

As you might imagine, skyscrapers made of soil, hay, and water aren't the sturdiest. Shibam's impressive structures are constantly threatened by wind, rain, and heat erosion, as well as by mankind. The city's citizens work hard to protect their unique dwellings, but the city took great hits during both a tropical cyclone and a violent civil war. As a response to war damage throughout the world, the 1954 UNESCO Convention on the Protection of Cultural Property in the Event of Armed Conflict stated that "damage to cultural property belonging to any people whatsoever means damage to the cultural heritage of all mankind." Shibam is no exception—just look at it. Wouldn't you agree?