AlUla Heritage Village, also known as Ad-Deerah, is the traditional Arabian village to which people of the oasis moved some eight centuries ago and inhabited until the 20th century. It was built on a higher part of the valley in order to be clear of the floods that can occur during the rainy season. At its maximum expansion the town contained more than 1000 houses, which were built adjacent to one another, thereby forming a wall around the town to defend the population.