Mecca, the Islamic holy city where millions flock every year, is constructing the world's largest clock. It's being built this very minute, but started counting time yesterday for the beginning of Ramadan.
Saudi Arabia is hopeful they're going to set a new time standard, the Mecca time, which will rival Greenwich Mean Time as the new prime meridian.
The clock is located very centrally in the city, close to the Grand Mosque, and is positioned on a skyscraper some 380m high—with the actual height of the skyscraper being 577m. This makes it six times larger than the Big Ben tower in London, apparently, and can be seen 17km away in evenings.
The four clock faces are 46m in diameter, and lit up by 2m LEDs, which flash green when the five prayer sessions should commence each day.
Not just a clock tower, the skyscraper forms a cluster of seven towers which will contain a shopping mall, some 2,000 hotel rooms, enough space for 30,000 to pray in, and even two helipads. [Foreign Policy via io9]