The Circle line name was not used officially until 1936 – but its existence is fundamental to the Tube’s early beginnings.

Their shared goal was to link the two lines together in a circle under central London. Over the coming weeks, we’ll be using maps to tell you the story of each of London’s Tube lines.

Opening five years after the first Tube services of the Metropolitan Railway, the line was built by the Metropolitan District Railway. The tunnels were made by digging a long trench, laying track and ...

The District line has 60 stations and spans from Upminster ... with the aim of completing a circle of underground tunnels in central London. But by 1870, the two railway operators split ...