The Bujang Valley, or the Lembah Bujang, Kedah, is sometimes referred to as the Ancient Wonder of Kedah. It is a rich historical site covering an area of about 400 sq km in Merbok. This archeological site was the site of an ancient Hindu-Buddhist kingdom that ruled the region from the 4th century AD. Over 50 Hindu and Buddhist temples had been excavated here. Artifacts and relics found at the site, dated back to the 4th century.

The archeological research at Sungai Batu, Lembah Bujang, Kedah by the Centre for Global Archeological Research, Universiti Sains Malaysia in 2009 found an early South East Asia civilization complex. The architecture of this complex includes building for ceremonial activity, jetty platform, hall and iron ore smelting center. The complex was already in used by the end of the first century, around the year 110AD. This finding uncovered the early technological architecture in South East Asia; the iron ore smelting technology in the early second century AD. In addition to the architecture structure, other artifacts found include potteries, beads, inscription and stone utensils. The Civilisation of Sungai Batu Complex suggests the rewriting of the South East Asia History.