Why is the Metro shaped like a pretzel?

The Tyne and Wear Metro is a marvel of the British railway network: the only true metro system outside of London and Glasgow 1 , with fully accessible stations, beautiful typographic design , and only the occasional closure because someone stole all the copper wiring again. But amongst railway nerds, it is also known for one more puzzling detail: it’s a pretzel. 1 Many sources describe it as a…