Someone's published a map of how many steps it takes to walk between inner London tube stations:

You'd think they'd get one of the basic tourist gotchas right – it does not take 822+1,275 steps to get from Queensway to Bayswater… That route probably involves walking to Notting Hill Gate, turning round, going back past Queensway and up the road to Bayswater! I'm a bit dubious about Euston to King's Cross St Pancras being under seventy steps less than Euston Square to Kings X too, plus they're ignoring the District / Hammersmith and City version of Edgware Road, thus meaning you can't see what they reckon it would take to walk the Circle Line.

A more useful map would show the number of steps needed to make the changes at the various interchanges. Some are trivial 'cross the platform' ones, others are hikes in themselves.