You need to get the Northern Line to Leicester Square and then the Piccadilly Line to London Waterloo.
The London Underground did give the East London line to the London Overground to ease its traffic.
On the London Underground map, the Circle Line is coloured yellow.
Central Line
The Circle Line Unfortunately this answer is wrong! According to Transport for London the only tube line to connect all London Underground lines is the Jubilee Line.
Hammersmith and City.
It's on the BAKERLOO Line.
Jubilee Line.
Hammersmith & City line
Black.
Green is the District Line
The red underground line typically refers to the Central Line on the London Underground. It runs from west to east across London, connecting various key areas and stations. The line is notable for its extensive coverage and is one of the busiest lines in the network.
How many feet underground is the Circle Line in London, UK