In five weeks time, the London Overground goes orbital. The South London link from Surrey Quays to Clapham Junction opens on Sunday 9th December, and suddenly it'll be possible to ride round the capital via only orange trains.
It's already possible to use TfL's Journey Planner to check the timetables for mid-December and discover (with a bit of digging) which trains are travelling where when. So here's my map of new Overground frequencies once the new line opens, including the typical number of trains per hour during the day.
The greatest boost will be on the line through Whitechapel, which rises from 12 trains an hour in each direction to an impressive 16. That's 4 trains an hour to each of the southbound destinations, running at 15 minute intervals. Trains from New Cross and West Croydon will terminate at Dalston Junction, while trains from Crystal Palace and Clapham Junction will run on to Highbury and Islington.
This creates the tantalising prospect of being able to ride the entire orbital route from Highbury and Islington to Highbury and Islington via Clapham Junction in only two trains. All the most hardcore London train geeks will be doing it, although the rest of you might give it a miss because it is essentially pointless.
The first train via Overground South is currently scheduled to leave Highbury and Islington at 07:11 on Sunday morning, arriving at Clapham Junction just after eight o'clock. Swap trains and you can continue your clockwise Overground journey around the capital, if engineering works play ball, returning to Highbury and Islington by 09:13.
Or you can do the whole thing anti-clockwise. The first train from Clapham Junction via Peckham Rye leaves at 07:20, arriving at Highbury and Islington at 08:13. Here you can catch a train on the existing route via Willesden Junction back to Clapham Junction (although again there are mixed messages about engineering work at Kensignton Olympia which might delay you by an hour or two).
Watch out for Next Train Indicator confusion. If you're at Highbury and Islington there are going to be trains to Clapham Junction leaving two minutes apart from different platforms travelling in different directions. Meanwhile at Clapham Junction there'll be two trains labelled Highbury and Islington, one clockwise, one anti-clockwise, leaving at virtually the same time. Let's hope there's some simple way of being absolutely certain which train's which, because it would be awful to end up in Peckham when you meant to go to Hampstead (and vice versa).