There was a long pause as my sister and I surveyed what can only be described as a building site and stood, calculating just how much time we would have to spend here before we could hoof it for the exit turnstile.

Before us, some 70 or so diggers and dumper trucks were crammed into what seemed like a tiny parcel of land; the M2 thundered over the Medway River and the occasional Eurostar zipped past, so close you’d think it was part of the park.

It was a sunny, relatively mild spring day, although the wind stung our faces and brought with it dust that settled in our hair and on our clothes. “Hmm, this looks fun,” my 11-year-old niece, Charlotte, muttered sarcastically. Not much of a theme park, I thought.

Diggerland was born in 2000 after Hugh Edeleanu, chairman of the plant-hire company HE Services, saw how his clients’ children were itching to climb on the JCBs on a company fun day. Everything on site is a real piece of machinery, some arranged around small enclosed courses you drive around, others fixed to the ground. Safety is paramount and there are plenty of staff on hand to demonstrate and control the diggers.

Though the aesthetics didn’t please us girls, already my seven-year-old nephew, David, was jumping up and down with excitement; his brother Andrew, 9, exhibited a slightly cooler enthusiasm.

So we climbed on to the first of an army of banana-yellow diggers to test our skill in hooking duck decoys and knocking down skittles before we were up to scooping up mud. Trust me — it’s not as easy as it looks to achieve the nonchalance of the workman in the road, swinging the arm of the digger to get maximum scoopage, while munching on a sarnie at the same time. I found it tricky juggling two levers, one back and forth and one up and down, while containing the excitement of my 16-month-old son, Christian, who was bouncing up and down on my knee.

By this time, I was warming to the idea of a day with the diggers, though it wasn’t until I was allowed to drive the mammoth JCB, kids packed in tight and my sister looking worried from the sidelines, that I really felt the thrill.

This was fun. We bumpity-bumped over a muddy assault course of devilish dips and trenches just waiting to tip us over — all 8.5 tonnes of us. So what if I couldn’t park this £45,000 beast properly and we had to squelch through the mud — it’s a lot bigger than my car.

The dumper trucks were a similar test of my driving skills. This time, I had David on my knee — unlike his siblings, he was too small to drive them on his own — and between us, we managed to mount the tyres in the middle of the course and then perform a ten-point-turn to round the bend.

“You’re so slow,” Charlotte shouted from behind, proud of her own driving skills and desperate to overtake.

Still, at least we didn’t go round like one unfortunate child, who seemed to have his elbow jammed on the horn for the whole course.

After that, there was the gut-wrenching Spindizzy, which does what it says on the tin, whirling you around in a dumper truck’s bucket. One to try before lunch, which by the way, was a very reasonable price as theme parks go (£20 for three kids’ meals and three sandwiches).

One niggle, though — there wasn’t much specifically for little people at the park. One corner housed a shady sandpit, while another had a few plastic tractors in a very poor state of repair.

Still, Christian loved watching the diggers. And we loved playing on them. By late afternoon, we literally had to drag my youngest nephew (“that was brill”) from the machines. My sister was reminiscing about a dumper truck she and I had played in as kids.

And as for my hard-to-please niece — “It was a lot better than I thought,” she said. Praise indeed.

Need to know

Diggerland (0870 0344437, www.diggerland.com) has parks in Kent, Devon and Durham. A fourth in Castleford, West Yorkshire, opened yesterday.

Entry costs £12.50pp (£11.25 online); free for under-3s. The parks are open on weekends, Bank Holidays and during the school holidays.

Age and height restrictions apply to different rides and can be viewed on the website; most can be enjoyed by children over 5. Toddlers can sit with adults on some rides, and there are some toy tractors and a sandpit.

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