There are lots of ways to measure this, including how many boroughs have I been to (all of them), how many bus routes have I ridden (all of them), how many stations have I visited (almost all of them) and how many places have I been to (pretty much the lot, depending on the list). But for a proper measure I need something a bit more comprehensive and a lot less subjective, so I've gone for squares.
The Ordnance Survey cover the country with a grid of squares - at the highest level 100km×100km which wouldn't be terribly useful for assessing intra-London coverage. Far better to use 1km×1km grid squares because they're properly granular, so all the better for distinguishing between 'nearly been to Chislehurst' and 'genuinely been to Yeading'.
My first job was to count how many 1km×1km grid squares there are.
I decided not to worry about the squares on the boundary. Some of these are almost entirely in London but others are tiny slivers with zero public access, so rather than get obsessed with fractions far better to discount the lot. I therefore ignored this black rim and focused on the undivided remainder in the middle. By my calculations there are 1463 1km×1km grid squares entirely within Greater London, a massive total, and how brilliant would it be to have visited the lot?
I had a fair amount of spare time during lockdown so I made myself a spreadsheet and then I coloured it in.
It soon became apparent that there are several kinds of 'visit'. The gold standard was to have visited on foot, to have stepped at least once inside the perimeter of the square. Other squares I'd only ever driven through in a vehicle, generally a bus, car or coach, so technically I'd seen them if not properly been. One rung down the ladder were squares I'd only ever been through by train, and if none of the above applied I had a genuine virgin square. I used yellow if I'd walked it, green if I'd been driven, blue if I'd only been by train and red for entirely unvisited.
Here's what northeast London looked like at the start of the year. Home is the purple square and the bottom left hand square is Streatham.
Unsurprisingly, for someone who's walked all over London, it turned out I'd visited the vast majority of squares. Anywhere close to home I'd walked to by default. Central London was pretty much a given. Long distance paths like the Capital Ring, London Loop, Thames Path and Green Chain ticked off a surprisingly high amount. But I'd also stepped out of outlying Overground stations, ridden to the end of minor bus routes, yomped around on random borough excursions and followed a lot of unlost rivers which covered a lot more squares. Plus I'd deliberately been to hundreds of obscure places for blogging purposes, like tracking down level crossings in Havering or following the David Beckham Trail through Waltham Forest, and suddenly these ridiculous safaris paid dividends.
For me it turned out the vast majority of London was yellow - I'd been to about 93% of all the squares on foot. But there were still little random unvisited islands all over, because gridlines have no respect for local geography, so in some cases I'd very nearly been but not quite. Also some parts of London really are in the back of beyond, having no main roads, no bus routes and no railways, maybe only a few suburban streets or a couple of country lanes. If you're sitting there thinking "I bet I've been to more than 90% of the grid squares in London" I bet you haven't, because I only just reached that total by being a London obsessive over two decades.
The grid square I bet fewest Londoners have been to is TQ4790, which is the square I've marked with a thick black border. It's on the Redbridge/Havering boundary near Marks Gate and is totally agricultural. It contains no roads, no railway, nor even a single building of any kind, and can only be accessed via a minor unattractive public footpath. I've blogged about it solely because it's so atypical, and you would have to be similarly dogged (or very local) to have been there too. Umpteen other grid squares are way off the beaten track and therefore woefully unfrequented (for example TQ0689, TQ4661, TQ5279, TQ5483 and TQ6085) but only TQ4790 is entirely undriveable.
Over the last few months I've been out to visit some of these green, red and blue squares in an attempt to turn them yellow. That ride on the 399 bus got me to TQ3797. A knitted postbox cover in Stanmore got me TQ1790. A borough triple point won me TQ4891. My visit to the hamlets of Hockenden and Kevington was mainly to turn two outlying squares yellow. Even tangential references to Ardleigh Green, Clayhall Avenue, Holders Hill, Ruislip Gardens, Sundridge and Woodcote Green weren't entirely coincidental. My blogging horizons have been properly boosted by visiting the unvisited.
This is how my coloured map looks now.
• It's now 95% yellow - that's 1386 of the 1463 grid squares.
• There are still 53 greens - that's squares I've ridden through but never stepped on.
• Only six squares are blue (i.e. train only, specifically on the Metropolitan line, beyond Orpington and south of Purley).
• And 18 squares remain red, that's 18 square kilometres I've somehow never ever been to.
I will continue to visit the green and blue squares to turn them yellow, so if you see a post about Tyler's Common, Mogden Sewage Works or Monks Orchard, that's what that's about. But mostly I have my eye on the 18 reds because these are unarguably unvisited.
Most of the reds are in Croydon or Bromley, unsurprisingly a long way from where I live. A few are on the peripheral northern edge of Hillingdon, Harrow and Barnet. I intend to report back on these rural outposts and suburban backwaters over the next few months. But I'll make a start with the two red squares nearest home - adjacent but mutually inaccessible - which I look forward to telling you about tomorrow.
It might take me a while to turn all 19 squares yellow, but how brilliant it'll be to have visited the whole of London.