Airports of London runways. Due to the location in London's western suburbs, Heathrow has had trouble trying to expand, with various expansion projects being cancelled.) As a result, the airport consistently runs at over 99% capacity and is often included on lists of the worst-rated airports in the world. However, on 1 July 2015 Heathrow's expansion plan was suggested as the best option by the Airport Commission and on 25 October 2016 a new northwest runway and terminal was approved by the Government. The airport is connected to Great Britain's motorway network via the M4 and M25 motorways, to London Paddington station by
Underground city boasts the city of Petra — "rose-red city, half as old as time" — carved from the living rock. Guanajuato city was built over old silver mines, some of which are used as roads. The Mexico DF metro system has many underground pedestrian walkways connecting stations. In general, many large railway stations house underground hallways featuring shops, restaurants, banks and money exchange offices. A striking example of such stations would be the main hallway of the Amsterdam central station, which connects to the city's metro system, although due to renovation and re-building it was temporarily (2012–2015) not possible to walk