Nick can barely contain his excitement. He's been bouncing up and down in the back of the car, chanting: "Diggerdiggerdiggerdigger!" ever since he was told that we are going to perhaps the world's most unusual theme park.
Diggerland, in County Durham, England, is a fantastic concept. It's essentially a big patch of dirt filled with construction vehicles, but all of the diggers, JCBs (such as backhoes), mini-loaders and trucks have been converted into rides of varying descriptions. It's heaven for little boys of a certain age. And in Nick's case, that age is 28.
With the entrance fee paid, he rushes straight for the nearest piece of yellow machinery. It's one of the smaller ones on display, a novel twist on a hoary fairground sideshow.
The digger's arm has a hook on the end of it and the aim is to use it to catch as many plastic ducks as possible from the pond beneath it.
We're all given brief instructions on how to move the arm around and manoeuvre the hook and then we whir and clank away.
It's utterly ridiculous, of course, but the competitive instinct instantly takes over and much goading is aimed at anyone not getting the immediate hang of it.
Once we've got the knack, we revert to being vile little brats. The aim becomes not just to catch the ducks but to lift them as high in the air as possible, then watch them plunge to death.
Either that or to smash them repeatedly into the ground. The other rides are equally bizarre. One is a carousel that has been built around a spinning JCB.
The operator must get horrendously nauseous within about five minutes of clocking on, let alone by the end of the working day.
Then there's one that gives panoramic views of the surrounding countryside by using a hydraulic lift, another where delighted children drive mini-loaders around in the mud and another where they can drive a police van.
The opportunity to drive at all is obviously a huge thrill for the children, although it wears thin quickly for the adults.
And that's where Spin Dizzy comes in. As rides go, it is a work of pure genius. It's one hugely expensive giant digger, with seats installed in the claw.
Once we're belted in, the man in the cabin, who has maniacal eyes, starts whizzing his victims around. It's a huge rush. And then the "Scooby-Doo villain" behind the controls starts getting evil, jerking us up and down, changing directions and generally turning faces green.
But the most pleasure is derived from the simplest concept: allowing punters to get behind the controls of a big JCB and scoop up lots and lots of mud.
Normally intelligent adults turn into awed simpletons as they pull up a claw full of muck, winch it as high as they can, then release it with a satisfying plop.
If Freud could see it, he'd have a field day. Well, unless he was too busy racing one of the dump trucks.