Streets Ahead: #Hampstead London's Skybox

Streets Ahead is the column from London Walks' Pen David Tucker…

In the book* I describe Hampstead as London’s “skybox”.

Has to do – inevitably – with geography. And geology. Geological events that “occurred” 750,000 years ago. The “single most important event in London’s history.”

Q. And that was?

A. The last Ice Age.  A glacier pushed down here. The Thames used to flow several miles north of London. Through what is today called the Vale of St. Albans. Our glacier diverted the Thames down to its present location.

Is that important? Strap it in folks: no Thames, no London. That important enough for you?

Over a very long period of time  – a geological span of time – the Thames carved out the Thames river valley.  It’s useful to think of the Thames river valley as a bowl of hills. Up here, in Hampstead, we’re ridge walking. We’re moving along on part of the northern rim of that bowl of hills. And with the route that I’ve fashioned for my Hampstead walk at two points I get my walkers to what I call “viewing platforms.” And from those viewing platforms you can see right across the Thames river valley. On a clear day you can see the southern rim of the bowl of hills, miles in the distance.

So how high are we when we’re at the summit? The precise answer is: 435’ 7” above sea level. (It’s probably a coincidence – but a very nice coincidence – that phone numbers up here, including mine, used to be 435 numbers.) Anyway, to put that 435’ 7” figure into perspective, when you’ve summited the soles of your shoes are 16’ 7” above the top of the cross on top of the dome of St. Paul’s Cathedral. So you’re up in the air a bit.

Now sometimes – not always – I take the matter a bit further. Ask my walkers, “do you want to know how far you can see from up here?”

Answer’s of course always a resounding, “yes, please.”

It’s one of those delightful, “gather round, children” moments. The walking tour equivalent of a party trick. A fun-to-know party trick.

I say, “ok, if you’re looking at a horizon and want to know how far away it is all you need to know is how far above sea level your eyes are. So for me – I’m 6’ 2” – I start with that figure of 435’ 7. I add to it my height. Round down a little bit because my eyes are probably only 5’ 7” from ground level. Add those two figures together – round them for the sake of convenience – my eyes are 441’ above sea level when I’m up on the roof of London.  Then what you do is multiply that figure – 441’ – by 1.5. Let’s do it. 441’ x 1.5 = 661.5. Final step, calculate the square root of that figure – the square root of 661.5. It’s 25.719, which we can round up to 26 miles.– that’s how far away that horizon is that we’re looking at when we’ve summited up in Hampstead.

And if you want to, er, take it a bit further, there’s another fun little calculation that beckons. If you can see 26 miles in all directions you’re casting a beady over 2,123 square miles. That’s arrived at by squaring the 26 mile radius – the distance out over London to that far horizon – and then multiplying 26 squared by pi (26 x 26 x 3.14 = 2123).

And if, up there, you feel like the lord of all you survey – and feel pretty good about that – well, so you should. 2,123 square miles is a big patch of ground. Greater London’s only – only – 607 square miles. 2,123 square miles is bigger than every county in England except Lincolnshire, Devon and Yorkshire.   It’s 2 ½ times bigger than Cambridgeshire, for example. A whole lot bigger than Cornwall’s 1349 square miles.  Three times bigger than Hertfordshire’s 727 square miles.  Nearly five times bigger than the 465 square miles that make up Bedfordshire.  (Extraordinary to think that London dwarfs the county of Bedfordshire and is nearly as big as such Home Counties as Berkshire and Hertfordshire.)

Tempted? You should be. It’s pretty special, London’s “skybox.” There’s a lot to see up there. And lot to be seen from up there.

* London Walks, London Stories



David leads the Hampstead walk this Sunday at 10:00a.m meeting at Hampstead tube



A London Walk costs £10 – £8 concession. To join a London Walk, simply meet your guide at the designated tube station at the appointed time. Details of all London Walks can be found at www.walks.com.