Stephen said "I will be running from station to station sequentially, rather than attempting some kind of approach where I could easily 'land grab' approach most of the stations in Zone One but then finding it increasingly difficult as I move further out. Also note I will cover each point-to-point as it covers a different tube line. Lots of the District and Circle lines overlap; nonetheless I may be covering quite a bit of the same ground twice!
Here are the eleven Underground Lines, in order of track length:
1. Waterloo & City - 2 stations (2 track miles)
2. Victoria Line - 16 stations (13 track miles, 15 miles point-to-point)
3. Bakerloo Line - 25 stations (15 track miles, 18 miles point-to-point)
4. Hammersmith & City - 28 stations (26 track miles, 19.5 miles point-to-point)
5. Circle Line - 35 stations (17 track miles, 23 miles point-to-point)
6. Jubilee Line - 27 stations (23 track miles, 39 miles point-to-point)
7. Northern Line - 50 stations (36 track miles, 40.9 miles point-to-point)
8. District Line - 60 stations (40 track miles, 47.4 miles point-to-point)
9. Metropolitan Line - 34 stations (42 track miles, 50.9 miles point-to-point)
10. Piccadilly Line - 53 stations (44 track miles, 57.3 miles point-to-point)
11. Central Line - 49 stations (46 track miles, 60.1 miles point-to-point)
There is also the Docklands Light Railway which I'm including in scope for the challenge:
12. Docklands Light Railway - 40 stations (21 track miles, 25.9 point-to-point miles)
So far Stephen's completed 10 runs. As he works during the week, most of his running is done at weekends or on days off. If he ran continuously it would involve 66 hours of running, or just under 8 1/2 days running for 8 hours non-stop.
You can keep up to date with his progress on his blog or if you want to donate, there's an online fundraising page or you can meet him in person on the last Tuesday of each month to quiz him about how it's all going.