The Persuasive Case for Getting a Little Lost

Great Britain has 246,500 miles of public road. Motorway accounts for 2,300 of them, which is 0.9% of the whole, and A roads for another 29,600. Everything remaining — 214,600 miles, or roughly 87% of the network — is B road, C road, or the unclassified lanes that the Department for Transport files under the flat heading “C and U”. Those are the figures as at April 2024, published by the DfT in February 2025. Almost the entire British road network is small roads.

A routing engine holds all of it and has no opinion about any of it. Given a destination it will produce the fastest line and a sequence of instructions, and the instructions are the problem. They are complete. There is nothing left for the driver to work out, and after a decade of compliance a good many of us have quietly stopped working anything out at all.

Motorway 2,300

A road 29,600

B road 18,900

C and unclassified 195,700

Total 246,500 miles. Minor roads (B, C and unclassified) account for 214,600 miles.

Source: Department for Transport, road lengths in Great Britain, 2024

What the Brain Does Unaided

The best evidence for what obedience costs comes from a paper published in Nature Communications on 21 March 2017: “Hippocampal and prefrontal processing of network topology to simulate the future”, by Amir-Homayoun Javadi, Hugo Spiers and six co-authors, and led from University College London. Twenty-four healthy volunteers navigated a simulation of the streets of Soho, in central London, while lying in an fMRI scanner. On the routes where they had to find their own way, activity in the right posterior hippocampus tracked the change in the number of onward connections available from each street they entered. Where a forced detour obliged them to re-plan, activity in the inferior lateral prefrontal cortex scaled with the planning demand.

The other half of the experiment is the interesting half. On the control routes, participants were, in the paper’s words, “instructed not to navigate and told which button to press at Decision Points”. The correlations vanished. No significant relationship between hippocampal activity and the street network; and planning demand at detours “did not significantly correlate with prefrontal activity” either. Told which way to turn, the machinery that models the road ahead simply did not engage.

When we have technology telling us which way to go, however, these parts of the brain simply don’t respond to the street network.

Mapped Since 1791

Britain was unusually well prepared for this. Ordnance Survey was established on 21 June 1791 under the Board of Ordnance, then the country’s defence ministry, its methods inherited from the military survey of the Scottish Highlands undertaken after the rising of 1745. The name is a garrison name. The first Ordnance Survey map, published in 1801, covered Kent, took three years, was surveyed at two inches to the mile and printed at one. From that came the two series most drivers can still picture: Landranger at 1:50,000 and Explorer at 1:25,000.

OS is now headquartered at Explorer House in Southampton, and its accounts describe the shift plainly. In the year to 31 March 2025 the paper map business turned over £7.4 million, down from £7.9 million the year before. The OS Maps app and website took £11.7 million, up from £9.5 million, a rise of 21%, on 508,000 subscribers against 477,000. Group revenue was £194.6 million. The screen overtook the sheet some time ago and the gap is widening.

We continue to see a migration from traditional paper maps to online mapping applications.

Trading line	2023–24	2024–25
Paper maps	£7.905m	£7.446m
OS Maps (app and website)	£9.546m	£11.679m
OS Maps subscribers	477,000	508,000

Source: Ordnance Survey Limited annual report and accounts, 2024–25

Where the Lanes Win

The failure mode is not abstract. Goudhurst, in the Kent Weald, sits on the A262, where the road narrows and turns hard through the village centre. Lorries routed along it have been damaging the place for years, including the churchyard wall. KentOnline reported in February 2026 that after a residents’ campaign backed by the local MP, Mike Martin, the Liberal Democrat member for Tunbridge Wells, three of the firms whose data underpins commercial routing — TomTom, Garmin and HERE — agreed to update their software so that heavy goods vehicles are no longer sent that way. Martin said he was pleased the satnav companies had listened to residents, and asked villagers to photograph any lorries still using the route.

The shape of that remedy is worth noting. One village, one A road, three companies, one negotiation, several years. It is a decent outcome and it does not scale. Great Britain holds 195,700 miles of C and unclassified road, and the DfT records 4,900 more miles of minor road in 2024 than in 2004, almost all of the increase in the C and unclassified category. No committee is going to walk it. Meanwhile the department’s traffic estimates for 2024 show 65% of all motor vehicle miles running on motorways and A roads, which are 13% of the network by length. Most of Britain’s roads carry hardly any of Britain’s driving.

Legal to Follow, Illegal to Hold

The state’s position on all this is more coherent than it first looks. Since 25 March 2022 the handheld offence in Great Britain has covered essentially any use of a device in the hand, closing a loophole under which drivers had escaped conviction for taking photographs, scrolling playlists or playing games because none of it counted as interactive communication. Government guidance is blunt: it is illegal to hold and use a phone, sat nav, tablet or any device that can send or receive data while driving. The penalty is six points and a £200 fixed penalty, rising to £1,000 in court, or £2,500 for lorry and bus drivers. A driver in their first two years loses the licence outright. A phone in a cradle remains lawful as a satnav provided it is never picked up and does not block the view of the road, which carries three points of its own.

And the following of instructions is now a tested competence. From 4 December 2017 the DVSA extended the independent driving section of the practical test to 20 minutes, roughly half of it, and most candidates spend that section following directions from a satnav the examiner supplies and programmes, a TomTom Start 52. One test in five uses traffic signs instead. A generation of British drivers has therefore been formally examined on obedience to a device it may not touch.

None of which is an argument for switching the thing off. It is an argument for arriving at the route ourselves now and again, which is a small and cheap pleasure and costs about twenty minutes. The destination goes on a 1:50,000 sheet, the obvious way to it is refused, and a line gets picked across the contours because of a river crossing, or a wood, or the fact that three lanes meet at nothing in particular. Four turns into memory; the rest folded into the door pocket. Ordnance Survey still leases vans for the field surveyors who keep those sheets honest. Someone ought to use their work.