Social networking site Facebook is to build its first data centre outside the United States in the northern Swedish town of Lulea, awarding an initial construction contract of US$ 121 million, reported Reuters. The data centre, set to be the largest of its kind in Europe, will take advantage of the climate in Lulea, among the coldest in Sweden, to cool tens of thousands of servers. Swedish construction group NCC said it was part of a joint venture with two U.S. companies, DPR Construction and Fortis Construction, which had won a contract of US$ 121 million for the first of three server buildings in the data centre. The data centre will be the northern most of its size on Earth. It is Facebook's first in Europe and will serve more than 800 million site users. Facebook said in a statement it chose Lulea, despite its remoteness some 1000 kilometers north of Swedish capital Stockholm, because its cold climate would be good for cooling and that it could provide environmentally friendly hydro-power. The three server buildings will have an area of 28,000 square meters each. Construction takes place in three phases and begins instantly. The first building is to be operational within a year and the entire facility is scheduled for completion by 2014.

Some 2,000 years after they were first erected, Ancient Roman harbors made from concrete are still standing across Europe. Meanwhile, more modern constructions have proved far less durable. Finally, scientists have solved the puzzle of what made the ancient concrete so strong — and they think the discovery could make modern buildings more environmentally friendly. The results are published in American Mineralogist. Concrete used for ancient sea walls was made by mixing lime, seawater, volcanic ash and rock. Researchers have now discovered that elements in the ash react with sea water, which actually strengthens the material. Researchers discovered the Roman concrete contained aluminium tobermorite, a rare mineral that adds extra strength. When the Roman concrete was exposed to seawater, the tobermorite crystallised and spread. The researchers said that long-term exposure to sea water helped these crystals to continue growing, reinforcing the concrete and preventing cracks from developing.

One of the biggest homes in U.S. history is rising on a Los Angeles hilltop, and the developer hopes to sell it for a record US$ 500 million. Nile Niami, a film producer and speculative residential developer, is pouring concrete in L.A.'s Bel Air neighborhood for a compound with a 6,9 thousand square meter main residence and three smaller homes, according to city records. The project, which will take at least 20 more months to complete, will exceed 9,3 thousand square meters, including a 465 square meters master bedroom, a 30-car garage and a "Monaco-style casino," Niami said. Niami's project, on a 1.6-hectare hilltop lot, will have 360-degree views of the Pacific Ocean, Beverly Hills, downtown Los Angeles and the San Fernando Valley. Plans called for removal of almost 30,600 cubic meters of earth, the equivalent of an American football field covered by 6 meters of dirt. Niami's mansion is set to be the largest built in the U.S. this century, surpassing Versailles, a 8,3 thousand square meters chateau in Windermere, Florida, under construction for David Siegel, founder and chief executive officer of Westgate Resorts. Estates with views of the Los Angeles basin are the California counterpart to Manhattan's penthouses or London's Mayfair manors, drawing a global cast of financiers, technology tycoons and celebrities who collect trophy homes like works of art. Around the world, five properties sold for US$ 100 million or more last year, and at least 20 others have nine-figure asking prices, Christie's International Real Estate reported last month. The priciest home ever sold was a US$ 221 million London penthouse purchased in 2011, according to Christie's. The most expensive properties on the market include a US$ 750 million rancho in USA, a US$ 425 million estate in France's Cote d'Azur Villa Leopolda, an almost US$ 400 million penthouse in Monaco and a US$ 365 million London manor.