Medain Saleh is the largest conserved site, south of Petra, of the civilization of the Nabataeans.
Featuring well-preserved monumental tombs with decorated facades dating from the 1st century BC to the 1st century AD, the site also has cave inscriptions dating to a much earlier period.
Here are the better known ones: Mecca Mecca is the holiest city in Islam.
Religious tourism is already big business in Saudi Arabia, but as the kingdom continues to implement Vision 2030, the tourism sector will receive millions in investment from the government.
Some 18 million foreigners visited Saudi Arabia in 2016, but nearly all of these were participating in Umrah or Hajj.
Jawatha Mosque was the earliest mosque built in east Arabia around 629 AD.
Although most of the mosque's original structure has disappeared, five small brick arches still remain.