The London Underground: yes, it can a source of stress for many, yet it is a luxury we couldn’t live without. So we can thank this day, 15 December, in 1906 for giving us the GNP&BR line (the Great Northern, Piccadilly and Brompton) which later became known as the Piccadilly line. Initially this line definitely proved a source of misery for its creators: it didn’t generate the footfall they had hoped and in its first year saw only 26 million passengers, less than half of the 60 million predicted. A few stations were closed in the 1930s due to low traffic, but the lead up to World War II saw an escalated (ahem) use as stations were used as shelters.When it opened in 1906, the GNP&BR’s line (not a particularly catchy name) served 22 stations and ran for 14.17 kilometres (8.80 miles) between its western terminus at Hammersmith and its northern terminus at Finsbury Park. Good old tube.