tim and Siddy explore the disused parts of Piccadilly Circus. Widely regarded as being at the heart of the capital, this station has always been the flagship of the London Underground. It’s grand, it’s opulent, it’s art deco. But it wasn’t always this big. A major expansion in the 1930s involved extraordinary feats of engineering to ensure the tube continued running and the traffic on the busy road junction above wasn’t disrupted.