 The layout of the Maya towns and cities, and more particularly of the ceremonial centers where the royal families and courtiers resided, is characterized by the rhythm of immense horizontal stucco floors of plazas often located at various levels, connected by broad and often steep stairs, and surmounted by temple pyramids.Under successive reigns, the main buildings were enlarged by adding new layers of fill and stucco coating.Irrigation channels, reservoirs, and drains made up the hydraulic infrastructure.