I've been cycling to work the last week, which is both excellent and exhausting. From the north (far) side of Potters Bar to Euston/Kings Cross is 14.1m/22.5km by the most direct road route. High Barnet, at the edge of London and just before Potters Bar, is the highest point between central London and York (!), halfway up the country. This means that the route has a few ups and downs. Getting to work in the morning is easier (going from 190m altitude to 80m) than the reverse in the evening. It's just over an hour to get in to work, and maybe an hour and fifteen minutes home. This has the advantage of saving me £170 in train fares monthly, and not requiring more time in the morning or evening to exercise, so I have more time to play with little V!
All this exercise is good build-up for the Fleet Half-marathon which I'm doing this Sunday. It's a pity I haven't been cycling for longer ... nonetheless, I'm pretty sure I can make a sub-2-hour time on this. Watch this space!