By around 788 BCE, a large settlement had been established on the northern bank of the Merbok River. The settlement was one of several in the Bujang Valley, covering the Merbok and Muda Rivers, about 1000 square miles. The Merbok settlement was built near the estuary of the tributary river, the Sungai Batu. Around 170 CE groups of Hindu faith arrived at Kedah, joining them soon were peoples from nearby islands and from the northern Mon-Khmer region. At the same time traders from India, Persia and Arab, arrived the brink of the Malacca Strait, using Gunung Jerai the Kedah Peak as marking point. Ancient Kedah covered the areas of Kuala Kedah, Kuala Bara, Kuala Pila and Merpah.