I'm not debating that. London is over x2 the size of Hamburg. Towns that are in zone 4 are around 15km from the center of London, in zone 6 it's close to 30km.

I'm not debating that. London is over x2 the size of Hamburg. Towns that are in zone 4 are around 15km from the center of London, in zone 6 it's close to 30km. I live in London and commute everyday, I'm acutely aware of the cost of travel in the city.