Saudi Arabia laid the foundation stone for the King Abdullah International Gardens (KAIG) in Riyadh, with plans for the facility set to include the world's largest botanical gardens. KAIG, one of the largest environment projects in the world, will be spread over a total area of 2.5 million square meters along Riyadh-Jeddah Road. Construction work of KAIG has started after the completion of the first phase of the project, which included leveling the site and fencing works. There will be six main sections at KAIG, including covered and open facilities. They are the Plants Gardens, the Valley Gardens, the Scientific Gardens, the Water Gardens, the International Gardens, and the Nature Gardens. The covered facility, which will be the largest of its kind in the world, would have two giant botanical gardens spread over a total area of 100 thousand square meters. The crescent-shaped facility will be five times bigger than the world's largest geodesic domes at the Eden Project, Cornwall, in Britain (). Its structure and fabric are capable of adaptation to the various environments. The project will focus on local plant life in the Arabian Peninsula and is designed to appeal to families and tourists. KAIG's open facility will have plants growing in the local environment, in addition to an open museum for plants, seeds bank, and rocky garden. There will also be research institutes, office accommodation, shops, restaurants, visitor facilities and a theater. The gardens will use recycled water and alternative energy supplies, exploiting solar and wind power as well as rainfall through collection tanks.

The Saudi Arabian government awarded US$ 22.5 billion in contracts to three foreign-led consortia on Sunday for the design and construction of a metro rail system in the capital Riyadh. The project, which will involve six rail lines extending 176 kilometers and carrying electric, driverless trains, is the world's largest public transport system currently under development, Saudi officials said. U.S. construction giant "Bechtel Corp" heads a group which won a US$ 9.45 billion contract to build two lines, the government announced. A consortium led by Spain's "FCC" won a US$ 7.82 billion contract for three lines, while Italy's "Ansaldo STS" heads a group that won a US$ 5.21 billion order. Design work will start immediately and construction will begin in the first quarter of 2014, the government said. The project would be completed in 2019. Designs for the Riyadh Metro call for 35.2 kilometers of twin-tube bored running tunnels and a further 13.7 kilometers of cut-and-cover work for a total subsurface length of nearly 49 km. Preliminary designs of the 176 kilometer metro system have been carried out by consultants Dar Al-Hanasah of Lebanon and Egis Rail of France. The Riyadh Metro or the so-called "Miracle of the Desert" consists of six main lines running a total length of 176 km with 94 stations, including 85 main stations, four transfer stations, and five park-and-ride stations. The proposed metro passes through areas near government buildings, commercial and health centers, educational centers and major universities in Riyadh and its suburbs. The metro will also connect the King Khaled International Airport (KKIA) through the city center and densely populated areas of Riyadh. Trains on the six lines will run at 40 km/h. All stations and carriages will be air-conditioned. The driverless electric trains will also be divided into first class, family class and single class carriages. Designs for the major stations were unveiled by the authority in May, with UK-based architect Zaha Hadid's design chosen for a station at King Abdullah Financial District, Norway's Snohetta chosen for a Downtown (Qasr Al-Hokm) station and Gerber Architekten of Germany's designs picked for a new hub station at Olaya.

In order to serve its rapidly expanding population of more than five million, the ArRiyadh Development Authority has commissioned Zaha Hadid Architects to construct the new King Abdullah Financial District (KAFD) Metro Station in its capital city of Riyadh, Saudi Arabia. Best known in Britain for her design of the Olympics Aquatic Centre, Hadid has again envisaged a curved structure, with the station's undulating form supposedly referencing Saudi Arabia's desert sand dunes. Measuring 20,434 square meters in size, the huge space will feature four public floors as well as two levels of underground parking and is intended to function as a gathering place as well as an interchange. A number of gangways and route within the structure will be incorporated to alleviate congestion and the station will also be connected to the Riyadh monorail via a skybridge. Looking more like the inside of five-star hotel, the proposed network, in Riyadh, Saudi Arabia, will boast a space age design featuring marbled walkways, gold-plated walls and, naturally in one of the hottest places on earth, air conditioning. The facade will apparently be designed to let in light while keeping out the harsh desert sun, while the overall shape is meant to recall the country's wind-blown sand dunes. King Abdullah has instructed the new Riyadh Metro be completed in four years. Prince Khaled bin Bander, the governor of Riyadh, said the project is progressing to plan and the ArRiyadh Development Authority has released details of the city's public transport plan including the six metro lines that will serve as the backbone for public transport in the city.

The world's largest solar thermal system for water heating recently opened in Riyadh, Saudi Arabia. The new one is almost double the size of what was previously the largest solar water heating facility (located in Denmark), and it will generate enough power to heat water for a university of 40 thousand students. The Millennium Energy company was responsible for the design and build of the solar thermal plant and the GREENTecONE, an Austrian solar design company, supplied the solar panels for the project. The 36 thousand square meter rooftop system is the size of five soccer fields and was built at a cost of US$ 14 million. The solar technology is just one of the many features that will make the new US$ 11.5 billion Princess Nora bint Abdul Rahman University for Women in Riyadh a showcase for environmental innovation. The project is also a signal that countries in the Middle East, which have become wealthy thanks to fossil fuels, are now planning for post-oil future. Plentiful sun shines down on Saudi Arabia, and the solar panels that allow this project to run are massive. Each one covers 10 square meters and weighs 170 kilograms. The panels have a transparent coating to enhance their performance, and they also require a special mounting system to keep them bolted to the roofs when Saudi Arabia's notoriously vicious sandstorms hit Riyadh. Watch for similar projects to appear in Saudi Arabia the coming decade. The Kingdom has set a goal for 10 percent of its energy to come from solar power by 2020. Currently oil is plentiful, and over half of Saudi Arabia's electricity comes from the country's black gold. But with oil pricing at over US$ 100 a barrel, it makes economic sense for Saudi Arabia to reduce their dependency at home and export more of it abroad. With the country expected to grow even more in the coming years, Saudi Arabia could become a global leader in solar power generation. The $14 million renewable solar energy development includes a 36,000 square metre rooftop solar energy system that will cater to the hot water needs of the 40,000 students at the city's Princess Noura Bint Abdulrahman University for Women. The 10 square metre solar panels have been provided by Austrian firm GREENTecOne. After a six month trial period, each one of the six solar fields has been uncovered and six tanks of 150m3 have been built to store excess solar heat at 110 C.