Stations that take a case
The South Ken subway has lifts; use it on a museum day. Paddington, King's Cross St Pancras, London Bridge, Westminster and Waterloo are the large stations. Lifts follow that day's TfL status — if one is down, use a neighbour. Covent Garden is a deep stair; with a case, walk from Leicester Square. The Elizabeth line is the Heathrow arrival. Do not add an airport express on top.