The basic materials used in the construction of the walled city included ausubo wood, limestone, sandstone, sand and metal. Bricks were used not only to build walls, but also for the framework of windows and doors in the rough walls. Limestone was burnt to produce lime, the material which bonded the mortar mixture used to tightly bind the bricks. The mortar was then painted with limewash.

Wood was indispensable. It was used for the temporary living quarters of the workers, for scaffolding, for building, for tables, chairs and many other uses. Wood was brought from the island’s forests to make windows and doors. The padlocks and other more complicated manufactured items were brought from Spain. Rope was also important. The thick rope was imported but the thinner types were woven from dry native grasses or from leather.

Iron was the most commonly used metal. With it, they made tools, locks and bars for the windows. Lead was used to anchor metal in wood, for waterproofing arches and for sewer systems.

One of the first tasks in construction was to provide temporary shelters for the workers and the materials; in this way, small villages sprang up close to the forts.