Question: How do I optimise my exit or entry from tube to exit or entrance?

Samantha Durbin answered on 7 Jan 2020:

At a practical level, you have to know your stations and choose where to get onto the tube to get off by the right exits. I tend to use landmarks on platforms to help me get it right. You also need to know about the flow of people at your target stations – for example, will the up escalator be on your side of the platforms? Will you need to navigate around barriers? Will you need to rush for a lift? The best thing to do is to do trial the journeys you want to be able to make quickly, like journeys to work or school, making things a bit better each time.

For example: I know exactly where to stand at both North Greenwich (by a particular bench) and Canning Town (by a particular map) so that when I get to Green Park I’m in front of the exit archway furthest from the escalator, meaning I get off the platform super quickly but have a good angle of approach to the bottom of the up escalators (if I were to try to get out exactly by the bottom of the escalator I’d get stuck in the crowd, as I’d also need to cross the people getting off the down escalator). If I know which way the trains are going on a platform, I can also work out where to get on so that I can get off by the up escalator at North Greenwich as I know I need to be at the back of the train going east, and the front of the train going west.

It is possible to work it all out using mathematical models, but I’m not sure that information ins publicly available. If you can build a model of the station, you can use something called “agent-based modelling” to include representations of how people will move around the space and find optimal paths. I did hear rumours of an old book that told you where to get onto a tube to minimise your getting-off time for every station in London, but this meant the passenger distribution in the tubes was dangerously uneven and the book was taken out of print. But I’m not sure how true it is!

When I was in Japan earlier in the year, all the journey planners I was using told me which carriages to stand in for the exits I wanted or changes I wanted to make, and where each carriage would stop was clearly marked on the platforms on pretty much all the subway and metro trains. You also got the stations marked on the map on my phone, along with the exit numbers (though it did get confusing when there were multiple levels as it wasn’t overly clear what was underground). It was a great system, and one I wish we had here!

If you’re interested in this kind of thing, check out The Londonist and in particular Geoff Marchall’s YouTube channel.