Green is the District Line
The Hammersmith and City line
The Central Line.
The Circle line is yellow
The Jubilee Line.
Bakerloo line
On the London Underground map, the Circle Line is coloured yellow.
Hammersmith & City line
Green is the District Line
Y The Piccadilly Line
The Piccadilly line in the London underground is dark blue.
The London Underground did give the East London line to the London Overground to ease its traffic.
The Circle line is 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.
You need to get the Northern Line to Leicester Square and then the Piccadilly Line to London Waterloo.
Jubilee Line.
It's on the BAKERLOO Line.