Saudi Arabia unveils high-speed Mecca-Medina train

"The journey between the Haramain (two holy mosques) is now shorter and easier than at any time before," said Nabil al-Amoudi, Saudi Arabia's transport minister. "The project highlights the kingdom's commitment to serving Islam and Muslims."

Pilgrimage is the centrepiece of bin Salman's tourism push. The hajj, one of the five pillars of Islam every able-bodied Muslim who can afford it must do once in their life, brings in billions in revenue for Riyadh's coffers.  

Over two million visitors performed hajj this year and 6.5 million performed umrah in 2017. Riyadh is looking to boost these numbers to 5 and 15 million respectively by 2020.

But the annual hajj is also Riyadh's biggest logistical challenge, and the ruling al-Saud royal family stakes its legitimacy on its management of Islam's holiest cites - King Salman's official title is the "Custodian of the Two Holy Mosques," at Mecca and Medina. 

The worst incident occured on 24 September, 2015, when a stampede killed at least 2,426 people. 

The new Mecca-Medina route was built by a Spanish-led consortium and was financed by the kingdom's sovereign wealth fund. It will cut the travel time between Islam's first and second holiest cities in half.

Riyadh is also investing tens of billions in infrastructure including mega-hotels to support the tourism drive. 

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