Arriving in Harwich Port. Any suggestions on travelling to the Covent Garden - Picadilly Line in London? Transfers etc.
The train station is right at the port. Get on the train and take it to the Liverpool station and then to Covent Garden.
From Liverpool Street take the Central Line to Holborn. Transfer to the Piccadilly Line and take it one stop to Covent Garden. Go here for a zoomable Tube map.
Get the train to Liverpool STREET station in London. If you ask to go to Liverpool in Harwich you'll be directed towards the city of Liverpool in north-west England.