An alternative measure to “max square”

There has been a discussion about how to take account of “inaccessible squares” in the max square challenge (¬† ).

Here is what I wrote so far on this. Plan to expand this with more examples of the clump idea.

“I agree with Nils that it raises the prospect of endless debate about what counts as inaccessible. E.g. someone on Facebook already posed the question about dual carriageways – certainly many people don’t like riding on them for good reasons, but they are not inaccessible. It just adds extra motivation for a 4am Sunday ride.

“Similarly there are very-hard-to-visit places – power stations, large factories, some military areas. I have the germ of an idea that we could set up something like the Association of British Tile Cyclists (or something similar grand, or indeed for Belgium). This could be an “official” entity that can make access requests which may be more successful than individual requests. It would also be an way of setting up occasional group rides which have a stated goal of tiling a particular area (so frustrating when you do a sportive that misses a few out in the middle…. ūüôā )”

“Having said all that, there are going to be areas where even the most determined can’t get to – there are military areas where even the military don’t go – e.g. firing ranges of certain types have a build up of unexploded unordances. You’re not going there, even on an open day. So, the idea of some sort of different metric does have some appeal. But those proposed on Facebook, e.g. “98% of 40×40″, are also unsatisfying. It is difficult to have a leaderboard comparing 100% of 38×38 versus 98% of 40×40. And we all like a leaderboard :-)”

“So I’ve been fumbling around for an alternate metric. Of course one possibility is just “total tiles” as already reported by VeloViewer. Another possibility, is to define a “clump”. A square is in your clump if you been to that square and to three of the four adjacent squares. Then measure how many squares are in your clump. This clump measure rewards people like Phill and Eric who have been to huge swathes of their area, but which aren’t square-shaped. It is also quite robust against a single hole due to an inccessible. But it is doesn’t reward a single track of squares. E.g. if you just cycled from London to Paris you clump size would be near zero as all you have is a long streaky path – you haven’t been “everywhere” in that area.¬†




Squartasrophe! Squarpocalypse! Squarmageddon!

Yes the date of Wednesday 14th June 2017 will live long in the memory of avid square-fillers. I was casually doing my daily VeloViewer refresh when a glance at my “max square” field on the summary had me choking on the contents of my bidon. Having rather smugly expected to see my recently-achieved “50×50” shining back at me, the colour fell from my face at the sight of a mere “20×20”. Surely some mistake??

I frantically switched to the map view on the activities tab, switched on Explorer mode and zoomed in. There it was in red and slightly paler red… my square was a shriveled up ghost of its former self. Dotted amongst the old, lost square dozens of squares were now showing as unvisited. I zoomed right into them and, sure enough, ¬†none of the ride lines actually DID go into those squares. But the day before they had shown as visited… so.. had I been there or not? What was going on?

In truth Ben Lowe, the magnificent impresario who makes VeloViewer happen, had warned us that the squarpocalypse was coming in this RideEveryTile post (further warnings in this Facebook post ).

Previously the algorithm for deciding what squares you have been in had to cope with the fact that it was only using summary data from your Strava data. This led to the possibility of squares being visited not being counted (e.g. if a road was a bit bendy, nipped into a square and out again, then the summary straight line might not capture this). Now people don’t like missing out on hard-earned squares, so Ben worked-around the issue by allowing a “buffer” of 100m around the squares. But this mean instead of false negatives (visited squares showing as unvisited) it allowed the possibility of false positives (unvisited squares showing as visited just because you’d been within 100 metres of them).

Now Ben has been able to implement a more accurate algorithm that can truly determine whether a particular ride goes through a particular square (I think by looking at all the Strava data, not just the summary). So there is no need for the buffer anymore. So Ben removed it.

And all us tilers discovered how much we had (almost certainly accidentally) been relying on the buffer to grab us a few squares!

[19th June 2017: Edited to add: The above makes it sounds like Ben forced this change upon the tiling community Рthis is not true Рhe did get the express 100% approval before going ahead. Also Ben has now put out his own blog post on the new algorithm Рhis post is sure to be far more accurate on the details than this one]

All is not lost

It is possible to recover some squares without even leaving the house!

Though the buffer is gone, all your previously uploaded rides still have the squares data associated with them that was generated using the old summary-data-only algorithm. This means you can end up with situations as shown in the image below:


The bottom left square is shown as unvisited, but you can tell from the ride track which road I must have been on, and that road takes me through the bottom left square. Unfortunately the old algorithm didn’t capture this. However help is at hand. Simply double-click on the red line to load the details of that ride. Whilst you reminisce about what a lovely ride that was, behind the scenes the data for that ride is being refreshed to use the new accurate algorithm rather than the old. If we now go back to the map page and force-refresh the page (I used Ctrl+F5 in Chrome), we find the square is now showing as visited:


Of the 2500 squares that previously made up my 50×50 square, 58 of them were showing as unvisited without the buffer. By selectively refreshing a few rides to use the new algorithm, this has come down to 45.

It’s not really the apocalypse is it?

Whilst most of who’ve been building up our max square for many months will surely have some momentary disappointment at it all seemingly disappearing, in truth it is almost the apocalypse – it is a great thing. Here presented to us on a plate is a copper-bottomed excuse to go out and visit more squares. Properly This Time.


As dawn broke the day after the apocalypse, I got right on with doing them Properly This Time. By extending my commute by a mere 10 miles, I was able to pick up a square that I’d never been to before (Strava link ; the new square is the little nubbin close to A3/M25 junction)

CS9 : Part 3

CS9 was mentioned tangentially in an email from City Hall following ¬†new(ish) Walking and Cycling Commissioner Will Norman’s interview in the Guardian¬†today. The email (quoted more fully on¬†) says “Consultation on Cycle Superhighway 9 (the route from Kensington Olympia to Hounslow) will take place in the summer (including tackling Chiswick Roundabout / Kew Bridge Junction)”.¬† With Hammersmith gyratory plans now post-consultation ( my notes are here ) it is good to know that the Kew Bridge to A4 run, the next most¬†crazy bit of the A315 commute, will also eventually be tackled.


CS11: My notes

TfL is still dithering on whether to go ahead and reduce rat-running in Regent’s Park by closing some of the gates to motor traffic some of the time.

Sadiq Khan is on the record a number of times¬†of saying he will “learn the lessons from earlier schemes” – which seems to delay and delay whilst he tries to figure out how to please everyone.

The face of the opposition to CS11 is “two swimming pools” Jessica Learmond-Criqui. (Articles about the swimming pools issue e.g. here, here ¬†and here tend to give her the name of her husband – i.e. Jessica Stokel). Every anti-CS11 stunt, such as claiming in the The Stage that the eldery won’t be able to go to the theatre because bus route 13 will now stop at Victoria rather than Aldwych to dressing up school children in surgeons’ masks to rage against polluting effects of cycle lanes has been organised by this one person.

Should TfL really be held to ransom by the noisy antics of a single well-connected and well-funded NIMBY?

[Some pro-CS11 folk claim in comments to various news articles that Ms Learmond-Criqui herself drives around the “narrow streets” of Hampstead in a Range Rover or similar “Chelsea Tractor”. I have seen no evidence of this.]


Strava and Apple Health bugs

TLDR: if Strava suddenly thinks you’ve changed gender, check your Apple Health settings.

A couple of days ago I got a few of my rides flagged on Strava. It was slightly mystifying as the roads were fairly ordinary rides with no GPS glitches or anything like that to give me virtual badges beyond what I’d earned.
Then I uploaded a ride yesterday and was surprised to take a bunch of top 10s! Wow I must be in unbelievably good February form!! And then I noticed I had picked up a QOM. Yes with a ‘Q’. Checking the settings I saw that Strava did indeed think I was female. My suspicions turned to the japers at work – they know I’m permanently logged into Strava and spend too much time route planning of post-morteming. 

Then today I got an email stating that my QOM on another segment had been “stolen”. Back to the settings, this time on the mobile and I see that every time I try to change to male, it automatically switches back a couple of seconds later to the fairer sex.

Lightbulb moment – a week or so ago I had connected Apple Health to Strava and never having set the former up properly it thought I was female and moreover took precedence over the correct setting in Strava. Fixed now.

But as of today at least, there is a stupid off-by-one bug across Strava and Apple Health so that if I set my Date of Birtu correctly in Health, then it appears as one day too early in Strava… Fortunately this will only effect one day every five years when I’m in the wrong age category a much less disruptive then the various QoMs I’d been advertently pinching – apologies.

CS9: Hammersmith gyratory

TfL has published the results of their two consultations on whether to add a two-way cycle lane to the north side of the Hammersmith gyratory ( Full PDF ). The main conclusion is that the scheme will go ahead with construction commencing this Autumn and finishing “in 2018”. The main change to the scheme from that consulted on is that the pedestrian crossing from the middle of Shepherds Bush Road into the middle of the gyratory (where the shopping centre/tube station is) will be retained at the cost of reducing space for cyclists to wait at the lights there.

This scheme is a prep-step for CS9, we hope. I use this route on my commute. For me individually I expect it will significantly increase journey time Eastbound – given the highly aggressive nature of some drivers when you choose not to use cycle lanes (cf East West Superhighway) it is dangerous not to use them. But there are more traffic lights and these will be cyclist-only so designed for slow progress again as with EWCSH. Further we will expected to use the extended contra traffic cycle lane on Kings Street. This will require slow progress (the pedestrians and motorist simply don’t look in the “wrong” direction, so you have to proceed on the basis that something will move into your path at any time). So slower and perhaps more dangerous – not a great combination eastbound. Westbound I am more positive. Yes the average speed will again be slower, but on the other hand I won’t have to go round the gyratory itself so I’m hopeful the increase journey time will be at worst small. Better, this westbound journey should be safer than the current situation. The only possible way round the gyratory at the moment is to take the middle of the appropriate lane all the way round . This saves you from much of the extreme late and unsignalled lane changes from motorist but at the cost of the occasionally irate person behind you (not that cars ever make faster progress than a bike as a whole round the island) The segregation will remove these stresses.

All in all the schemes are not for cyclists who’ve already chosen to cycle in the existing conditions, but to encourage others who want more segregation. For this reason I am supportive of the scheme even though, overall, it impacts me personally slightly negatively.

London borough speed limits

Within each London borough some roads are maintained by the local borough council and others are maintained by TfL as part of Transport for London Route Network (TLRN) – typically these are the major/arterial roads. Limits are in flux at the moment with limits typically dropping from 30 to 20mph over the last 7 years or so. 20mph limit areas are¬†more pleasant to cycle in my opinion (motor traffic doesn’t quite feel the same right to roar pass you if you are doing approximately the speed limit yourself). So I decided to track which boroughs are the cyclists friend.

(“all roads” means “all borough roads not necessarily TfL roads”)

Borough Policy Ref
Barking and Dagenham No policy (March 2015)
Barnet ¬†No plan to bring in broad 20mph limit. Some roads 20mph for “historic” reasons. Some expansion near schools ¬†
Bexley  Some very limited 20mph in Bexleyheath centre. No plans for expansion May 2016.


Brent ¬†Some 20mph areas “case-by-case basis” ¬†
Bromley ¬†Note¬†in the Bromley Times article Chairman refers to minutes of council meeting June 2015 for details of policy, but¬†I can’t actually find the discussion in the minutes at

Found a pro-driving/anti-20mph group called Bromley Borough Roads Action Group who Were certainly strongly opposed in 2008 Рseems to have folded into the ABD in 2009.



Camden 20mph limit all roads since December 2013
Croydon ¬†Plan to gradually implement 20mph all “residential” roads. 5 zones. Zone 1 live. Zone 2 expected to go live April 2017. ¬†
Ealing  20mph limit in Acton area for year from September 2016 as a pilot
Enfield ¬†Some roads here and there are 20mph, but “less than 10% of borough roads” (2014) ¬† (10% quote)

Several roads “hit with” 20mph limit (Enfield Independent)

 Hackney 20 mph all roads since July 2015
Hammersmith and Fulham Proposed all non-TFL roads. Actually decided to do 20mph on all side roads and 3 town centres, remaining main roads 30mph  LBHF Cabinet meeting 9 March 2016
Islington 20 mph limit all roads since January 2013. Enforcement since 2014.
Kensington and Chelsea Firmly pro motor vehicle:

All roads “30mph or lower” (i.e. 30mph) and do not support lowering to 20mph – “only consider schemes where high speeds are a constant problem and where the police agree to undertake regular enforcement”

Further “demand on road space […]¬†makes it impossible to allocate road space to specific vehicles such as buses or cycles”.

Further “also not possible to provide shared use on most pavements […] or to provide cycle paths” – though note the current consultation on Sloane Street is to widen the total width of pavement from 8.5m to 10m whilst continuing to provide no provision at all for cyclists.

It also goes on to say there are no speed cameras¬†on any borough road and that it seeks to remove existing traffic calming measures (speed humps). It has also “maximised the amount of parking spaces available”
Lambeth 20mph limit all roads since April 2016
Lewisham 20mph limit all roads since September 2016
Southwark 20mph limit all roads since March 2015
Tower Hamlets  20mph limit all but one road (Leamouth road near Canary Wharf); trial made permanent September 2016
Waltham Forest
Westminster ¬†20mph trial agreed at council meeting September 2016. Limited to “areas near schools and other areas with history of speed-related accidents”.

But note section 4.3 in link: “It is clear that a blanket approach of 20 mph has not worked
City of London  20mph limit all roads since July 2014