Tube quiz (1)The longest loop
What's the longest unbroken tube journey you can make without repeating yourself? That's a journey which doesn't pass through any station more than once, never passes through a gateline and joins up with itself at the end.
Don't worry, I'm not going to ask you this question because I've answered it myself, and ridden it just to check.
This, I reckon, is the longest unbarriered loop of unique stations. It meanders all over zone 1 because that's where the most interchanges are, and incorporates circuits out to West Ham, Stockwell and Rayners Lane. Altogether it passes through 97 different tube stations, which is 36% of the overall total, and it took me 26 separate trains to complete. Also it looks like a giant flapping bird. You can click on the map for a closer look.
I'm a bit annoyed it's 97 because it'd be better to have reached a round 100, but I couldn't find any way of upping the total. I did manage to tick off every station inside the Circle line except Regent's Park and Russell Square, plus all but five around the edge. I couldn't loop out to Finsbury Park because that would have meant doing King's Cross twice, and I couldn't do Royal Oak to Goldhawk Road because there are gatelines either side of the road at Hammersmith. It's a good puzzle but sorry, I've solved it for you (unless you're the smart one who chips in after ten minutes and tells me I could have done better).
Instead my question is this. How long do you think it took me?
Answers to the nearest 5 minutes, thanks. comments
I started at Bow Road, obviously, and went round clockwise. I did it at the weekend when the trains were behaving themselves and the only engineering works were on a branch I didn't need. To help you with your estimate I spent 50 minutes interchanging between platforms and 1 hour 20 minutes waiting for trains. Half my waiting time was doing the twiddles at High Street Kensington and Liverpool Street, not helped by a Circle line train being cancelled. The longest interchanges were at Green Park and Paddington. The longest journey was from Acton Town to Rayners Lane. And I took a good book with me so the time wasn't all wasted.
Importantly, because this is a journey without any gatelines, it should only be tackled by someone with a Travelcard. If I'd tried to do it on Pay As You Go I'd have exceeded the Maximum Journey Time and been charged a maximum fare of £8.90, not just at the start of my journey but also at the end, and that'd be £17.80 down the drain. TfL fares aren't designed for dicking about on the tube, and dicking about is exactly what the longest unbroken loop requires.
n.b. If you take away the requirement for an unbroken loop then a longer journey is possible. Break the circuit between Mile End and West Ham, then start at Epping and end at Upminster and you can get the total up to 126 different stations. But I didn't try that, and I recommend you don't either.
So what's your best guess for the total duration of my 97 station journey? Add it to the special comments box further up the post (and any more general thoughts on the broader challenge in the normal box below). And at 7pm I'll come back and tell you who got closest.
Tube quiz (1) The longest loop
