Old Walled City of Shibam, the "Manhattan of the desert"
Background
Shibam stands in Wadi Hadramaut, in the Hadramaut Governorate of Yemen.
UNESCO inscribed the Old Walled City of Shibam in 1982 under cultural criteria (iii), (iv) and (v).
It is a 16th-century city surrounded by a fortified wall and laid out on a rectangular grid of streets and squares.
Its tower houses are built of sun-dried mud brick and rise up to seven storeys from the cliff edge of Wadi Hadramaut.
These towers earned the city the nickname "the Manhattan of the desert".
Shibam was historically a caravan halt on the spice and incense route.
Its Friday mosque dates mostly from the 9th and 10th centuries and its castle from the 13th century.
UNESCO records flooding, decay, the abandonment of traditional flood management and the replacement of mud with concrete as threats; the site has been on the List of World Heritage in Danger since 2015.
In plain words
Wadi — A valley or stream bed in a dry region that carries water only after rain.
Sun-dried mud brick — A building block of earth shaped by hand and hardened in the sun rather than in a kiln.
Caravan halt — A stopping place where a trading party rested on a long overland route.