Pompeii is located on a plateau formed by the Vesuvius volcano's lava flow. The city dominated the valley around the Sarno River, the delta of which hosted a busy port.
Information about the origins of the city are uncertain. The oldest available traces date back to the 7th-6th Centuries BC, when the first tuff walls, called pappamonte, were built to enclose an area of 63.5 hectares. A mixed population of Etruscans, Greeks and other Italic peoples led to the city's development.