Today's post is about travelling one stop on the tube and how much it costs.
Normally a one-stop journey lies within one zone so costs a minimum amount. Certain boundary stations are officially in two zones so it doesn't matter which direction you go, it's still a one-zone journey. But where adjacent stations lie either side of a zone boundary your one-stop trip has to pass through both so will cost more.
For example, here at the northern end of the Northern line there are three cross-boundary stations - Hendon Central, Hampstead and Archway - and three other boundaries where no interface station exists. 18 possible one-stop journeys are shown on the map, of which as many as 15 lie entirely within one zone. But three of the one-stop journeys cross two zones, namely Edgware → Burnt Oak, High Barnet → Totteridge & Whetstone and Finchley Central → East Finchley, so cost more. They're not even the three longest journeys, which are Golders Green → Hampstead, Colindale → Hendon Central and Highgate → Archway, but each of these involves a cross-boundary station so remains within one zone.
I'm going to try to answer two questions, which are... a) What's the shortest one-stop tube journey that passes through two zones? b) What's the longest one-stop tube journey which remains in one zone?
n.b. I'm using a database of distances between tube stations that TfL kindly released a while back.
n.b. Distances are by train, not as the crow flies.
What's the shortest one-stop journey that passes through two zones?
It's a tie, as it turns out, between Euston → Mornington Crescent and Aldgate East → Whitechapel. Both journeys cross the edge of zone 1, both are 820m long (which is just over half a mile) and both cost £2.40. I had to scroll through almost 100 shorter one-stop one-zone journeys before I got to these two. Euston does feel very zone 1 and Mornington Crescent and Whitechapel do feel very zone 2, so that's fair enough. You could argue that Aldgate East deserves to be zone 1/2 rather than just zone 1, but these things are very hard to tweak and it's not going to happen.
The shortest two-zone journey beyond central London is Northfields → Boston Manor which is in zones 3 and 4, closely followed by Eastcote → Ruislip Manor which is zones 5 and 6. Both journeys would cost £1.50 off-peak and £1.70 at peak times if they were in one zone, but they're in two so they cost 10p more. This is a 2021 thing. Last year every off-peak journey in zones 2-6 cost £1.50, but now a £1.50 fare is only for journeys within a single zone so cross-boundary journeys are more expensive.
Here are all the one-stop two-zone journeys of less than a mile.
• Euston → Mornington Crescent (z1→z2, 820m)
• Aldgate East → Whitechapel (z1→z2, 820m)
• Paddington → Warwick Avenue (z1→z2, 880m)
• Northfields → Boston Manor (z3→z4, 1000m)
• Eastcote → Ruislip Manor (z5→z6, 1140m)
• Northwick Park → Harrow-on-the-Hill (z4→z5, 1290m)
• Sudbury Hill → South Harrow (z4→z5, 1370m)
• Hounslow Central → Hounslow West (z4→z5, 1460m)
• Burnt Oak → Edgware (z4→z5, 1470m)
You have to go a lot further down the list before the first one-stop z2→z3 journey appears, which is Finsbury Park → Seven Sisters (3.1km). Indeed there's only one other one-stop z2→z3 journey, which is Hammersmith → Acton Town, and that's only because the Piccadilly line skips lots of stations. It turns out every other tube line has a boundary z2/3 station rather than skipping straight from one zone to the next, because whoever devised these zones was being much more generous on the z2/3 boundary than elsewhere.
Meanwhile there are no boundary stations on the dividing line between zones 4 and 5, not one, which means a one-stop journey from zone 4 to zone 5 will always cost that little bit more.
What's the longest one-stop journey which remains in one zone?
Technically the longest one-stop one-zone tube journey is the (currently closed) one-way section between Heathrow Terminal 4 and Heathrow Terminals 2&3. The Piccadilly line goes on a really longloop beneath the runways which is somehow over 2½ miles long, all of which is in zone 6. More realistically the distance is just under a mile as the crow flies, but it's also an impossible journey to make on foot (and not especially recommended for crows).
Here are the five longest one-stop one-zone journeys.
After the Heathrow loop these are all outside London, including three at the far end of the Metropolitan line where distances between stations are quite large. As for cost the Heathrow journey is free, thanks to the airport's free travel zone, and the other four all cost just £1.50 off-peak. As one-stop trips go, these are bargains.
Staying within Greater London, here are all the other one-stop one-zone journeys over 1½ miles in length.
• Hounslow West → Hatton Cross (z5, 2.9km)
• Wembley Park → Kingsbury (z4, 2.9km)
• Mile End → Stratford (z2, 2.8km)
• North Acton → Hanger Lane (z3, 2.5km)
• Heathrow T23 → Heathrow T5 (z6, 2.5km)
• Boston Manor → Osterley (z4, 2.4km)
• Canada Water → Canary Wharf (z2, 2.4km)
• Gants Hill → Newbury Park (z4, 2.4km)
• Bank → Waterloo (z1, 2.4km)
The Heathrow arm of the Piccadilly line has appeared several times in these lists because it's full of anomalies. Travelling one stop from Hounslow West, for example, it's 2.9km and one zone to Hatton Cross but 1.5km and two zones to Hounslow Central... which is a shorter distance but more expensive. Similarly from Boston Manor it's 2.4km and one zone to Osterley but 1.0km and two zones to Northfields... again with the shorter trip costing more. And yes, in many of these cases it'd be better to walk than pay the higher fare, but not everybody has that option and geography often conspires against.
All of which only goes to confirm how capriciously confusing London's zonal fare system is. It mostly made sense when it was introduced in the 1980s but decisions to include boundary stations in some places and not in others have led to numerous anomalies that continue to this day. Just occasionally TfL add another boundary station (e.g. Kennington 2021, Stratford → Canning Town 2016), which only helps, but they couldn't do it everywhere without losing a lot of money. Short of throwing the whole system up in the air and starting again, which'll never happen, this complex mess lingers on.
