A live map of Britain's trains, some ploughing through the M25 and Channel
Signalbox put a real-time map of Great Britain's mainline rail online, every mainline service moving live in the browser.
The clever part is how Signalbox says it works: it identifies which train a phone is riding by matching a snapshot of the device's data to each train's trajectory, with no background location tracking and no hardware. Slick in theory.
In practice, locals weren't impressed. One watched a Liverpool Street service plough across the M25, forty miles off its route; another who lives beside a line calls the whole thing as good as useless.
A country's trains, guessed from phones and signals
Signalbox built a real-time map of Great Britain's mainline rail network and put it at map.signalbox.io. The page renders entirely in the browser, so there is little to read; the story is what moves on screen. Positions come largely from railway signalling data, topped up with algorithmic inference where the signals go quiet.
The company's own pitch is more ambitious than a timetable feed. Its technology, per a blurb quoted in the thread, "identifies the train a device is on by matching a snapshot of smartphone data to a train's trajectory data", with no background location tracking and no extra hardware. In principle it can tell which specific service your phone is riding.
The edges show the seams. Coverage is mainline and overground only: no London Underground, no trams or light rail, no heritage lines, nothing in Northern Ireland or the Isle of Man. The delay-severity colour scale tops out at 10 minutes, which flatters a network whose delays routinely run longer. And the station list is stale: Cambridge North, open since 2017, and Cambridge South, opened barely a week before, are both absent. Similar live maps already exist for railways outside the UK.
Trains through the Channel, and other impossibilities
The fun began when locals checked the map against geography they could see. One viewer reported a physically impossible commute:
I just witnessed a London Liverpool street service plough through the M25 motorway - about 40 miles south of it's typical route and 5 miles south of the nearest actual railway. Dozens of the trains seem to be traversing through the English channel/La Manche towards the north sea.
For at least one person the test was literally out the window. A commenter who lives beside a railway line ran the most direct check available:
I live next to a railway line so I'm in the (not particularly unique, and definitely not enviable) position to compare what's on the map to 'IRL' trains, and I can tell you it's as good as useless.
An embedded developer and former game dev spotted the tell in the aggregate:
I can tell it's not accurate because it has half the trains marked as on time. Reality is far more depressing.
That last line is why the project charms even as it fails: a map of British trains only convinces once enough of them are running late.
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