Architecture in the first Saudi state was characterized by a multiplicity of styles and a harmony consistent with the country's society. Each region was unique in its architectural designs inspired by the nature of its environment; the majority of houses during the era of the first Saudi state were made of clay, which was abundant at the time, and with other elements available in their natural environment, like stone or plants. The central region relied on mud, bricks, hay, stones, wood, tamarisk, and palm trunks in building the houses. Diriyah, for example, was famous for its palaces and mosques, such as Salwa Palace, "the symbol of heroism", and Al-Turaif Mosque, and these buildings were distinguished by the beauty of Najdi architectural designs. As for the western parts of the Saudi state, the style of building in Makkah was similar to that of Jeddah. The houses of Makkah were built of stones and had elegant architectural designs. Some of them consisted of three floors, and had many windows overlooking the streets, in addition to prominent latticed windows adorned with intricate wood works, also overlooking the streets. Among the many and varied dwellings in the south of the Arabian Peninsula, patterns were mostly "domed nests" whose stone bases were oval in shape, and the roofs were made of tree trunks and branches covered with tanned leather or with sails trusted with ropes. Some were made of stone brought from the mountains, finely chiseled and fixed with mud. The outer walls of the dwellings varied in material: some were made of stone, others of mud, yet others of a combination of both. The north and center parts of the Saudi state used to have similar construction and architectural designs, with houses often built of mud. Some of the dwellings there had some floors, and many had some kinds of towers, or were forts or palaces. The natural environment of the Eastern Region is also reflected in the architecture of its buildings, as was the climate, and one often finds difference in materials used in coastal and non-coastal regions. In the former, builders took advantage of marine rocks, while inland cities far from the sea relied on limestone extracted from the ground and rocks brought from hills for the foundations.
