Use of the site as a mosque began with the dawn of Islam's arrival in the region. The first major architectural undertaking dates back to 692AD and started with the construction of the mosque's outer walls. By the end of the eighth century the mosque's wooden columns had been replaced with marble columns and the wings of the prayer hall had been extended on both sides.

Over the centuries the mosque has been modified, rebuilt and expanded to accommodate growing numbers of pilgrims. The government of Saudi Arabia acknowledges 1570AD as the earliest date for existing architectural features of the mosque.

The latest round of extensions and modifications - 1988 to 2005 - involved the building of additional minarets, a residence for the Saudi monarch that overlooks the mosque, creating another prayer area, and the erection of nearly 500 extra marble columns. The Al-Masjid al-Haram with its nine minarets and vast expanses of public space presents a stunning spectacle.

Kingdom Tower

The Kingdom Tower is the highest mosque in the world and is in the heart of the capital of the largest Gulf nation, Saudi Arabia. This uniquely designed edifice is 303 metres high - Riyadh's tallest building - and was inaugurated in October 2003.

The glistening glass-clad tower has an elliptical footprint and is topped by a 120-metre-high catenary arch with a gallery at its apex.

The 56-metre-long skybridge atop the skyscraper, which bridges the two points of the arch, contains an observation deck and affords spectacular views of sprawling Riyadh.

The Kingdom Centre is the most prestigious business and residential address in the city, dominating the skyline of the capital's premier commercial district as it straddles the Olaya and King Fahd roads.

The Kingdom Centre is also a prime shopping destination. Two floors are for women and these levels are managed and serviced by women, affording female shoppers the option of shopping in complete and discreet comfort.

The kingdom centre is owned by Alwaleed bin Talal bin Abdulaziz Al Saud, a prince of the Saudi royal family, and the centre was awarded one of the world's most highly regarded prizes in architecture before it opened to the public.

The Kingdom Tower was the winner of the Emporis Skyscraper Award in 2002 and was described as the 'best skyscraper in the world for design', an accolade that no one in this Islamic kingdom has disputed.

Hajj Terminal

The Hajj Terminal at Saudi Arabia's King Abdulaziz International Airport in Jeddah houses, for a short time every year, more than 1 million pilgrims who make their way to Mecca through this entry point.

The 5 million sqft terminal is the world's fourth most expansive air terminal after airports in Hong Kong, Bangkok and Seoul.

The building is covered by a remarkable tent-style roof, a fabric-tension structure that covers 40.5 hectares and is made from a pioneering form of fibreglass especially developed for the job.

Tents have been a feature of the Arabian peninsula for centuries but the tent at the airport, put in place in the early 1980s, had never been tried before. In its basic design the terminal tent is similar to that of the Bedouin's traditional home - lengths of material slung between poles driven into the ground - but the similarity ends there. The terminal tent is 210 separate tents joined together and is not attached directly to the ground but suspended in mid-air, roughly six storeys high. Construction of the Hajj Terminal was a massively complex and ambitious undertaking and the project used more than 500,000 square metres of Teflon-covered fibreglass fabric imported from the United States.

National Commercial Bank building in Jeddah

The 27-storey National Commercial Bank building in Jeddah was the Saudi commercial capital's first high-rise, and has won a number of awards for its unique and inspired design.

The triangular plan of the main structure is repeated on all floor levels and in the windowless edifice there is a vast 'loggia', or garden, which provides views over the city. This loggia is visible from any part of the building's office space. It has the feel of an 'iwan' or mosque's vaulted space, or even an Islamic-style courtyard.

The dramatic 30-metre-wide facade openings were designed to provide daylight without direct sunshine and they open into a triangular courtyard that extends vertically through the building, providing ventilation and a significantly measurable cooling effect in this hottest of Red Sea cities. Lifts and services are grouped in a separate rectangular tower adjoining one side of the equilateral triangle that is the main building. The tower is capped by the executive floor which extends over the entire area of the triangle. The glass-walled executive offices on this top floor are shielded by a wall with patterned cut-outs covering a 60cm recess behind the building's outer surface. This feature is like the shuttered, screened balconies of traditional Saudi architecture.

The banking hall in the main plaza level also fully spans the triangle and has a mezzanine level supported on three columns that is bathed in diffused sunlight.

Hajj Terminal National Commercial Bank building in Jeddah