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Liz Breslin spills the beans on her trip to the formerly top-secret Bletchley Park.
Bletchley Park is just up the road from Bletchley train station, which as a child was the only thing I thought Bletchley had going for it: a ticket out of town. Returning to the area after decades away, I'm seeing a different side of the old place.
What's happened in the interim? To tell that story forward, first we need to go back, back to 1938, when Captain Ridley's shooting party showed up in Bletchley, ostensibly for a jolly old time at an estate close to the aforementioned station.
They were closely followed by the Golf, Chess and Cheese Society, although this, of course, was a cover too.
With war breaking out across Europe, the Government Code and Cipher School (see what they did with the initials there?) was set up secretly and urgently on the premises, in Milton Keynes, 80km northwest of London.
Cryptanalysts congregated to work out encoded enemy messages, such as those sent by the German Enigma machines.
Fast-forward to 2014 and Bletchley Park has just received a visit from the Duchess of Cambridge (whose grandmother was a BP girl) and an 8 million ($NZ16.5 million) grant to save and memorialise the site.
As well they should. After all, Eisenhower called their war contribution ''decisive'' and, by some estimates, the work done there shortened the war by between two and four years.
Bletchley Park said jump and Churchill asked how high. Well, that bit is not strictly true, but most times they said ''please'', he said ''Action This Day''.
It has been no mean feat to piece BP back together. Churchill wanted machines and paperwork destroyed after the war, some say lest it fell into Russian hands. The Official Secrets Act was upheld with pride and gravitas.
Careless talk costs lives, remember. Sisters who worked in different sections, separated by the makeshift huts on site, didn't share the secrets of their four walls.
Some couples who met at the park and later married never furnished each other with details of their activities. Many, given the time lapse, have literally taken their secrets to the grave.
So we enter this secret world through what was Block C and is now a gift shop, cafe and introductory exhibition. We spend some time browsing there, marvelling at the irony of using whizzbang touchscreen technology to explain to a new generation how the very origins of that technology came about.
Because it was at Bletchley Park that mathematicians Alan Turing and Gordon Welchmann refined and upsized a basic, Polish-designed Bombe machine.
And it was that machine that led to the creation of the Lorenz code-smashing Colossus, the world's first electronic computer, and so paved the way for our plugged-in generations to come. (The rebuilt Colossus can be viewed at the National Museum of Computing, which looks like it is part of the Park, but you pay a separate 5 entry fee to get in.)
Apart from the top tier of boffins, it was mostly women, Wrens, who served the war effort there, itemising information and churning out results on the noisy Bombe machines.
Discreet ads were placed to find people with the right skills: a crossword competition in the Telegraph was even used as bait.
People from ''good families'' were preferred and referred, particularly if they could speak foreign languages.
They were accommodated as far away as the rather plush Woburn Abbey.
A cycle rack is stacked full on site as a nod to the most common form of transport around the area.
With such social touches taken care of, it is easy to imagine the rush between day and night shifts, the Theatrical Society meetings outside, the joviality of the workers' canteen and Alan Turing parking up his rickety bike before unlocking his cup from his radiator and knuckling down for the day.
That the stilted rotations of his bike chain on the way to work helped him with his designs for the Bombe may be as much of an urban myth as the Apple logo signifying his choice of suicide method (cyanide-laced apple).
If there is a cryptology nerd heaven, it may be in Building B where, among the largest display of Enigma machines in the world, Turing and Welchmann's Bombe has been painstakingly re-created.
The original, by all accounts, was dismantled and sold for scrap after wartime activities ceased.
With more than 12 miles of wires behind the workings, that's a lot of scrap. It can only be described as a monster computational device.
Well, actually, it can be described in many more words than that, as I found out in conversation (more like monologue, to be fair) with two earnest brains attending a GCHQ centenary code-breaking challenge on site.
It's all to do with considering the likely strongest links, whirling the Enigmas and locking in the combinations with the Bombe.
My brain hurt just working that out: I don't think I am Bombe-running Wren material.
Imagine being stuck in huts resembling temporary school classrooms for hours on end with noisy machines or just the insistent scratch of pen on card for company. And you can't tell a soul outside what you're doing.
We poke our noses into some of the huts that have been restored. The small rooms now house exhibitions and reconstructions.
We read about how pigeons helped with the war effort and play probability on more touchscreens.
We head for fresh air, next to a pond-like lake. Turns out it is actually both: a lake reconstructed on the site of medieval ponds; a rather grand vista for the historical centrepiece of the park, the Manor House.
The walk there has the added bonus of sound effects, presumably to enhance the atmosphere.
There is a subtle thwack of balls as you pass grass tennis courts and I have to stop myself going back and forth under a tree that produces the tinny tones of an early car or perhaps a motorbike courier. Vroom! Ting ting!
The manor, called the Main House by most at BP, was home to Commander Alistair Denniston during the early war years.
His office and the library have been reconstructed.
Eager guides at the door are ready to accost us and thrill us with wartime tales.
Around the sides are a bookshop, sparsely stacked, a post office, closed, and a wartime toy and memorabilia museum/rummage room that smells of eau de musty grandmother.
It is enchanting, not least for discovering the story of Helena Butler, who made parachute silk knickers out of offcuts and embroidered them with ME109 planes coming down in flames and the motto ''They came down without a fight''.
We round off our visit with a sidestep to the stables and the Polish memorial commemorating the earliest Bombe creators.