Grand Central Terminal, NYC

https://en.wikipedia.org/wiki/Grand_Central_Terminal#Related_structures

https://en.wikipedia.org/wiki/Park_Avenue_Viaduct

https://en.wikipedia.org/wiki/Grand_Central_Terminal#Innovations

https://upload.wikimedia.org/wikipedia/commons/9/99/Grand_Central_Terminal_-_Sectional_View_1939.jpg

https://en.wikipedia.org/wiki/Grand_Central_Terminal#Terminal_City

https://en.wikipedia.org/wiki/Grand_Central_Terminal#Services

https://upload.wikimedia.org/wikipedia/commons/3/3d/RailUS_GCT-upperTracksPlan.gif

https://upload.wikimedia.org/wikipedia/commons/6/61/RailUS_GCT-lowerTracksPlan.gif

https://en.wikipedia.org/wiki/Grand_Central%E2%80%9342nd_Street_(New_York_City_Subway)#Station_layout

https://upload.wikimedia.org/wikipedia/commons/a/a8/Grand_Central_subway_1918.jpg