Specifically, which London borough adjoins the most other London boroughs?
Go on, guess.
(you'll never guess)
While you're guessing, allow me to explain the rules a little better.
A borough is defined to be touching if it shares a land border, however short, with any other. But when the border is the River Thames, I'm only accepting a 'neighbour' if there's a way to walk, drive or ride from one borough to the other. This cuts out Havering to Bexley, Bexley to Barking & Dagenham, and Barking & Dagenham to Greenwich, because cross-river connectivity in Outer East London is currently non-existent. It cuts out Lewisham to Tower Hamlets, which touch for half a mile mid-river near Deptford, but with no way across. And it cuts out Lambeth to the City of London, slap bang in the centre, but whose 100 metre border has no bridge, no boat and no tunnel.
So those were a few hints as to what's not going to be top of the list.
Actually two boroughs come top of the list, which doubles your chance of guessing correctly. And that's a shame really, because London trivia is always best when there's a single answer. I recognise that "Which two London boroughs have the most neighbours?" isn't as good a question as the singular, but unfortunately that's the reality.
Got an answer yet?
Or maybe you've already scrolled down far enough to see the map below, which means you've already spotted the answer. Sorry, these things are often surprisingly hard to hide.
Brent and Wandsworth are the London boroughs with the most neighbours, each with seven.
(sorry, it doesn't sound like quite such a brilliant nugget of London trivia phrased like that)
Brent's seven neighbours are Harrow, Barnet, Camden, Westminster, Kensington & Chelsea, Hammersmith & Fulham and Ealing, all adjoining on land. Wandsworth's seven neighbours are Hammersmith & Fulham, Kensington & Chelsea, Westminster, Lambeth, Merton, Kingston and Richmond, the first three linked across the Thames.
Here's a photograph of one of those boundary points, specifically the road junction where Brent meets Westminster meets Camden.
The shops on the left are in Brent, the street sign on the right is in Westminster, and the library in the background is in Camden. This photograph was taken in Kilburn, by the way, quite near Starbucks, at the junction where Oxford Road meets the Kilburn High Road. I will confess I've got three other similar photos, in three other triple-boundary locations around the edge of Brent - one from Kilburn Lane, one from Kensal Green Cemetery and one from Willesden Junction - but best I don't share these with you in case you think I'm taking this far too seriously.
I'll also confess that Lambeth and the City of London would also have seven neighbours if only I hadn't made up that rule about it not counting if there isn't a bridge. My apologies for muddying trivia perfection even further.
Most of the boroughs with six neighbours are in central London, which makes sense, because that's where they're most likely to be surrounded by others. But there is an exception, which is Bromley, which might be on the edge of the capital but is also London's largest borough, so has a lot of neighbours.
Meanwhile two inner London boroughs get by with only four neighbours, namely Kensington & Chelsea and Islington. Both are long thin boroughs sandwiched between two others, with only a small opening at either end, so aren't able to notch up a higher score.
The majority of Outer London boroughs have only three or four neighbours, which isn't surprising because they're on the edge of the capital. Obviously they have lots of neighbours outside London, indeed if we included these then Hillingdon and Enfield would both rise from three to seven, and Bromley would hit eight. But that's not the game we're playing, we're talking London boroughs only, such are the joys of trivial definition.
On these rules, the London boroughs with the fewest neighbours are Havering and Bexley, each with only two. Both these boroughs are stuck out on the eastern edge of London, hemmed in by the Home Counties and also the barrier of the Thames. If only someone would build a bridge or two out here, or dig a tunnel, or even chart a ferry, then these two boroughs would ratchet up from two neighbours to three or four. But as things stand, and for the foreseeable future, both Havering and Bexley are very much out on a London limb. I wonder if this helps explain why the populations of both often have atypically different opinions to the rest of the capital. And don't worry, that's as deep and meaningful as today's post is going to get.
To be fair, it is pretty much irrelevant how many neighbours a London borough has, indeed I've merely been stretching out a map to fill a lengthy post. But if anyone ever asks you in a pub quiz which London borough has the greatest number of neighbours, subject to certain waterway-related conditions, well, you might now have two good chances to score a point.