Secrets of the London Underground

Tim Dunn and Siddy Holloway explore the disused Jubilee line areas of Charing Cross station, now more famous as a film location.

Tim Dunn and Siddy Holloway discover the hidden world of the Waterloo and City, the only line entirely underground.

Tim Dunn and Siddy Holloway explore King William Street, the original terminus of the first electric Tube in the world.

Tim Dunn and Siddy Holloway walk the Piccadilly line at night to explore the hidden World War 2 remains of Brompton Road.

Tim Dunn and Siddy Holloway explore the disused parts of London Bridge. Siddy visits Ongar in Essex and nearby Blake Hall.

Tim Dunn and Siddy Holloway explore Kings Cross St Pancras, including a secret siding and the disused Thameslink station.

Tim Dunn and Siddy Holloway explore the brand new Elizabeth Line and have access to two of its stations weeks before the line opens.

Tim and Siddy visit Quainton Road in Buckinghamshire, 50 miles from London - and once on the underground. Siddy also explores Kingsway tramway tunnel.

Tim Dunn and Siddy Holloway visit the cathedral-like Greenwich Power Station, which stands ready to power the tube at short notice.

Tim Dunn and Siddy Holloway explore the tube ststaion with the most platforms, Baker Street.