Travellers in the Middle East do not have many options when it comes to moving around the region. Journeys between cities, separated as they are by vast expanses of desert, are almost always made by air. When travelling within cities, road transport is usually the only viable option.

There are some exceptions. North Africa has had operational railways since colonial times, and metros run in Cairo and Tehran. But generally the choice is a simple one: fly or drive.

This was fine when populations were small and economic activity limited. But as countries develop, a more efficient system is needed for people and goods to move around freely.

Governments are investing increasing amounts in alternative forms of transport. Ferries and water taxis are peripheral options for coastal cities, but most of the burden rests on new rail and metro systems.

The Gulf and North Africa are both investing heavily in high-speed rail links that will provide an alternative to air travel. Although it is unlikely that people in Muscat will ever elect to travel to Rabat by train, for example, it should be a popular alternative for shorter journeys.

Rail is also important within cities. As populations grow, immense strain is placed on the road infrastructure and cities inevitably grind to a halt in rush hours. The solution, which needs to be taken up more widely, is to build efficient mass-transit systems that will take commuters off the roads.