Mada'in Saleh is a pre-Islamic archaeological site in the Al-Ula sector in northwestern Saudi Arabia. Most of the vestiges date from the Nabatean kingdom and this site is the kingdom's southernmost and largest settlement after Petra, its capital. Accounts from the Qur’an tell of an earlier settlement of the area by the tribe of Thamud in the 3rd millennium BC. According to the Islamic text, Allah punished the Thamudis for idol worship and for conspiring to kill the prophet whom He sent, the non-believers being struck by an earthquake and lightning blasts. Even today, many believe it is a cursed place and will not go there. The government is attempting to overcome this belief. In 2008, Mada'in Saleh became a World Heritage Site.