Video shows moment Mexico City metro overpass collapses 01:56 (CNN)It s known as the Golden Line. The Mexico City subway system Line 12, spanning 25.1 kilometers (15.6 miles) and featuring 20 stations, was touted as one of the most expensive and ambitious public works projects in Mexican history when it was inaugurated in October 2012. It reflects a technological advancement and state-of-the-art features that can only be compared to the construction of the great metro systems of the world, a Mexico City government official boasted during the kickoff ceremony.
The highly publicized ribbon-cutting was attended by the who s-who of Mexican politics and power at the time, including then-president Felipe Calderón and Marcelo Ebrard, who was then in his last days as Mexico City s mayor and is now foreign minister. Carlos Slim, Mexico s richest man and owner of one of the construction companies involved, was also there.