The earliest archaeological evidence of human colonization in Sri Lanka appears at the site of Balangoda. These Balangoda people arrived on the island about 34,000 years ago and are identified as Mesolithic hunter gatherers who lived in caves. Several of these caves including the well known Batadombalena and the Fa-Hien Rock cave) have yielded many artifacts from these people, currently the first known inhabitants of the island.
The Sandakelum people probably created Horton Plains, in the central hills, by burning the trees in order to catch game. However, the discovery of oats and barley on the plains at about 15,000 BC suggests that agriculture had already developed at this eary date.
Several minute granite tools, (about 4 centimetres in length), earthenware, remnants of charred timber, and clay burial pots date to the Mesolithic stone age. Human remains dating to 6000 BC have been discovered during recent excavations around a cave at Varana Raja Maha vihara and in Kalatuwawa area.
Cinnamon, which is native to Sri Lanka, has been found in Ancient Egypt as early as 1500 BC, suggesting early trade between Egypt and the island's inhabitants. It is possible that Biblical Tarshish was located on the island. (James Emerson Tennent identified Sri Lanka with Galle).
Archaeological evidence for the beginnings of the Iron age in Sri Lanka is found at Anuradhapura, where a large city–settlement was founded before 900 BC. The settlement was about 15 hectares in 900 BC, but by 700 BC it had expanded to 50 hectares. A similar site from the same period has also been discovered near Aligala in Sigiriya.