By the 10th century, small oil wells dotted the shores of the Caspian Sea, according to the State Oil Company of Azerbaijan Republic (SOCAR). Europeans learned of the resource-rich area and began traveling to the Caspian Sea to investigate in the 16th century. The first offshore oil well was drilled in 1820. Today, the oil and gas industry is prominent in the area. Other businesses include salt extraction, fishing and tourism along the coasts.