Dammam is the capital of the Eastern Province of Saudi Arabia, the most oil-rich region in the world. The judicial and administrative bodies of the province and several government departments are located in the city. Dammam is the largest city in the Eastern Province, and the fifth largest in Saudi Arabia, after Riyadh, Jeddah, Mecca and Medina. It forms part of the Dammam Metropolitan Area; The Dammam metropolitan area, or greater Dammam, is the metropolitan area associated with the city of Ad Dammam, Eastern Province, and its suburbs. It is the area that is closely linked to the city through social, economic, and cultural ties. The Dammam metropolitan area: mainly known as greater Dammam, is the largest metropolitan area in the Eastern Province of Saudi Arabia formed by three main neighboring cities: Dammam, Dhahran, and Khobar these 3 respectable cities are sometimes referred to as the triplet cities.
The metropolitan area of the triplet cities has an estimated population of 4,140,000 as of 2012. Greater Dammam also includes many other smaller cities such as: Al Qatif, Safwa, and Ras Tanura. Dammam Metropolitan Area, and the rest of the Eastern Province, is served by the King Fahd International Airport (KFIA), the largest airport in the world in terms of land area (approximately 780 km2), about 20 km to the northwest of the city. Dammam's King Abdul Aziz Sea Port is the largest on the Persian Gulf. Its import-export traffic in the country is second only to Jeddah Seaport.
The origins of the name "Dammam" is disputed, some say that it is onomatopoeic and it was given to the area because of a drum positioned in a nearby keep, when sounded for the alarm (a melody called "damdamah") to alert the residents of returning fishermen's ships, others say that the name was given according to the Arabic word "dawwama" (whirlpool) which indicated a nearby sea site that dhows usually had to avoid.
Ad Dammam was first inhabited by a family from Al Bin Ali clan and a number of Persian Howela families in the early 1923. The Albinali family, led by Sheikh Nasir Ahmad Albinali, were invited by HRM the late King Abdul Aziz from Bahrain to come and inhabit Dammam. While the AlDossary families led by Sheikh Ahmed Ibn Abdullah ibn Hassan Al Dossary migrated from Bahrain and were given the chance to choose a land where to settle by HRM the late King Abdul Aziz. Ad Dammam was immediately chosen for its vicinity to the island of Bahrain as the clan hoped to head back there soon, but the British rule in the region made it very hard for them to move in every sense (divide et impera) so they finally realized they had to settle there for good. Years later, Sheikh Ahmed's brother moved south where he and his family settled in Al Khobar, which by that time was already inhabited. However this tiny episode gave to Khobar a population boost and close ties with the bigger city of Dammam.
When the modern Kingdom of Saudi Arabia was founded in 1932, the area was the site of several hamlets that depended on fishing and pearls for their survival. Over a span of a little more than half a century, the area has developed into a thriving hub of industry, commerce and science, and home to more than half a million people. The area's transformation was launched with the discovery of oil in commercial quantities. The Eastern Province sits atop one of the largest oil fields in the world, and it was here in Dhahran in 1936 that Aramco, the predecessor of the national oil company of Saudi Arabia, Saudi Aramco, dug the famous Dammam No. 7 well that proved beyond doubt that the Kingdom possessed a large supply of hydrocarbons.
The discovery of new oil fields to the south, west and north of Dammam in the 1940s and 1950s, which now account for a quarter of the world's proven oil reserves, triggered a building boom. The Albinali Family, led by Sheikh Muhammad Nasir Albinali and Brothers played a crucial role in the development of the city of Dammam and the Eastern province in various fields. Experts and technicians from throughout the Kingdom and the world gathered to help search for new oil fields and bring them on-stream. New pipelines had to be installed, storage facilities built and jetties constructed to handle tankers. The growing number of experts working in Dhahran required the building of housing, hospitals, schools for their children and other amenities. Before long, Dhahran, the corporate headquarters of Saudi Aramco, the largest oil company in the world, was spilling out into the desert in all directions.