atch your step!” warns Pedro Marfil. As we gingerly pick our way across the slate rooftop of Córdoba’s eighth-century Mezquita (Spanish for “mosque”), the medieval archeologist does not have to warn me twice. So what if we are a mere 21 meters (70') in the air? It’s still a dizzying drop, made more so by the broiling July sun. With each step, I hear thedisconcerting squelch of sandal-sole rubber melting underfoot in the 44-degree (112° F) heat. I think longingly of the cool, dark interior below, with its pillared forest of double-tiered red-and-white striped arches.
But Marfil is showing me the ingenious grid of gutters, pipes and miniature aqueducts once used to capture precious rainfall and channel it to giant cisterns (aljibes in Spanish; jubb inArabic) beneath the patio below. From the Middle Ages until the 1950’s, the patio was a cemetery, the derelict cisterns were filled with bones, and the runoff fed the fountains, he says. Now the patio’s well-ordered grove of cinnamon, orange, olive, palm and cypress trees has been restored to the glory it originally enjoyed under the Umayyad rulers, and the cisterns once again collect water for use inthe Mezquita. Up on the roof, on this blast furnace of a day, it is perfect weather for appreciating the historic Arab skill of trapping, storing and managing that evanescent, life-giving commodity, water.
Gesturing toward a towering wooden waterwheel a few hundred meters away along the broad Guadalquivir River, Marfil explains that it’s the ruined Albolafia noria, among the last vestiges ofthe masterful panoply of mills, dams, flood protection and canals that the Umayyads built between the eighth and 10th centuries. (The name of the river comes from the Arabic al-wadi al-kabir, “great river.”) Barely visible in the shallows are also the remnants of an imposing dam, a nearly three-meter-thick (10') barrier built of stone imported from North Africa and marble columns that once rosethree meters above the waterline. In the Islamic era, when the mills were in operation, trip-hammers attached to the axles of water-wheels pounded out paper pulp, husked rice and crushed sugarcane in a process imported from China.
Peering down the narrow street between the Mezquita and its neighbor, the Alcázar, a palace converted into a museum, Marfil traces the former path of an aqueduct, now longgone, erected on Roman foundations by ninth-century Caliph Abd al-Rahman ii to bring spring water from the Sierra Morena range, 80 kilometers (50 mi) west. By the 10th century, at a time when no city in western Christendom was larger than 10,000 souls, Córdoba boasted a cosmopolitan population of half a million, sustained by one of the most advanced water systems in the world.
Seven kilometers(4.4 mi) west of the city, among the sprawling ruins of Madinat al-Zahara, the garden capital built by Abd al-Rahman III, archeologists have uncovered evidence of a staggering 300 baths—many lavishly painted—as well as artificial fishponds, sculpted marble pools and basins fed by a network of aqueducts and subterranean canals.
Gravity-fed fountains embellish a courtyard at theheart of the Alhambra’s sprawling, elaborate Generalife Gardens in Granada.
rom the ninth through the 16th centuries, Islamic societies from Spain to Oman experienced a “golden age” of science and technology. One of the most important of these technologies is also today one of the least thoroughly studied: hydrology, or the control of the movement of water. The rise of cities like Córdoba,Damascus, Baghdad, Fez and Marrakech all required increasingly sophisticated methods of water management to supply rapidly growing populations. Integrating, adapting and refining irrigation techniques and water distribution methods from India, Asia and Rome, Muslim water engineers, starting as early as the seventh century in Arab countries and around the 10th century in Spain, built an agricultural...