*Click on photo for full-size image.
“Designed by John McAslan, it is intended to cater for much-increased passenger flows and provide greater integration between the intercity, suburban and underground sections of the station, as well as facilitating easier passenger exchange between the King’s Cross and St Pancras complexes. Passengers departing on trains at this station use the new concourse; those arriving on trains must exit the station from old concourse on Euston road. The architect claims that the roof is the longest single-span station structure in Europe. The semi-circular building has a radius of 54 metres and over two thousand triangular roof panels, half of which are glass. The steel structure of the roof, engineered by Arup, has been described as being “like some kind of reverse waterfall, a white steel grid that swoops up from the ground and cascades over your head”
Source: “All change at King’s Cross” by Kieran Long at the London Evening Standard, 14 March 2012.
The photograph was taken from the walkway between the mezzanine floor and the main station building during the evening rush hour. At the left of the picture, below the walkway, is Platform 9¾ where a Harry Potter fan is posing for his picture. Most passengers are in a hurry to catch their train home; those dallying are engrossed in their mobile phones.”
Summary from photo’s description on Wikimedia Commons.