The obligation to provide fresh water to the urban population led to the development of a distinctive public monument: the water fountain, or sabil. Sabils – of which a number were built by the Mamluks (r. 648–92 / 1250–1517) in Cairo and Jerusalem – consisted of an underground cistern and a chamber with window grilles facing onto the street at ground level. An attendant hired to distribute water in cups sat behind the grille and handed the water out to passers-by. The sabil-kuttab had a similar fountain arrangement, with the addition of a covered first-floor gallery which served as a children’s elementary school (kuttab).