With the massive increase in traffic that has ensued from the Kingdom's industrial and agricultural development, it has been necessary to upgrade many of the inter-city roads to expressways, with anything up to eight lanes for traffic. Some of the more important inter-city highways are;

• Dammam - Abu Hadriya - Ras Tanura Highway (257 kms

• Khaybar - Al Ola Highway (175 kms)

• Makkah - Madinah Al Munawarah Highway (421 kms)

• Riyadh - Dammam Highway (383 kms)

• Riyadh - Sedir - al Qasim Highway (317 kms)

• Riyadh - Taif Highway (750 kms)

• Taif - Abha-Gizan Highway (750 kms)

The cities too have become congested by the growth in traffic and a number of cities now enjoy the benefits of modern ring-roads which serve to speed vehicles on their way and reduce congestion and pollution in city centers.

A further development is the construction of networks of over- and under-passes within the cities which again serve to facilitate driving in city centers.

While a major effort has been devoted to inter-city and in-city road-building, agricultural communities have not been neglected. Even isolated villages are now connected by road to the main road network, so that the Kingdom can now boast a fully integrated, modern, nation-wide network of roads.

The climate and the terrain of the Kingdom are inimical to road-building. Burning hot deserts and high mountain ranges, each pose different but equally challenging problems for contractors. Nowhere were these problems more intimidating than in the south west of the Kingdom, where mountain ranges soar to 3,000 meters. A series of projects, involving the construction of magnificent viaducts, has been undertaken so that even the more inaccessible parts of the Kingdom in this region may now be reached by road.