The Eastern Region contains the Kingdom's massive petroleum resources. The headquarters of Saudi oil industry is located in this region in Dhahran, a few miles from the administrative capital and port of Dammam. Ras Tanura, the world's largest petroleum port, is located to the north of Dhahran.
A special weather phenomenon affecting chiefly the Eastern Region is the north-westerly winds called the Shamals. These are prevalent during late spring and early summer, reaching their greatest frequency in June.