Red Williams and family took the plunge for an action-packed stay in West Wales

M y lads screamed: "JUMP Dad - go on, jump!" I told the boys to take a running one as my heart burst out of my chest.

"I'll go when I'm good and ready," I fired back, as the two teens grinned.

Taking a deep breath, I leapt 25ft off the jagged rocks and plunged into the Irish Sea.

Salt water blasted up my nose as I sank beneath the waves – and the cold hit me like a battering ram.

Welcome to Coasteering – the latest bonkers craze to win over thousands of extreme sports fanatics and madmen like me.

We'd headed out west to the Wild West of Wales.

Cornwall, the Scottish Highlands, North Yorkshire, Northumberland, the Lake District, East Anglia – they had all been ticked off with my wife, Loraine, and kids.

Wales was the final frontier.

Summerhill Farmhouse, hard by a hamlet with the fantastic name of Stepaside, hove into view – a brilliant base for touring and exploring deepest Pembrokeshire.

Soaring up through a vertical carpet of deep-green ivy, the 200-year-old cottage was criss-crossed by wooden beams.

The three-bed Hoseasons farm was ideal for our gang-of-five. Summerhill was peaceful, relaxing and just half a mile out of delightful seaside resort Amroth. It marks the start of the stunning 186-mile Pembrokeshire Coastal Path.

Head west and you bump into the pretty beach hamlet of Wiseman's Bridge, set in a steep tree-strewn valley.

Minutes later Saundersfoot appears – and what a joy it is. The bustling seaside resort packs silky-soft sands, a busy little harbour, more shops than even Loraine's mum Lynn could tackle.

We pressed on into neighbour Tenby. And we were blown away by a town which has got to be one of the most idyllic and attractive seaside destinations anywhere in the UK. The iconic 13th century town wall, ruined Norman castle and miles of sandy beaches are all well known.

But the resort which attracted Victorian tourists in the 1800s exudes a charm and a grace which would win over the most hard-nosed, cynical visitor. We popped into the Blue Ball restaurant for dinner and at just over £100 for the five of us it wasn't the cheapest bite in town – but it was surely one of the best.

But all those calories had to be worked off.

So we made a beeline for Heatherton Activity Park, outside Tenby. With everything from paintballing to treetop trekking, you could spend a week there and still not do the lot.

First up was archery which was amazing once we got the hang of it.

We had a laugh playing crazy golf before having a pop at baseball, bashing each other on the bumper boats and trying out a giant high-speed Scalextric game.

We snaked our way across Pembrokeshire to Mathry, just above the country's smallest city of St Davids, for a heart-stopping Adventure Day.

About as far west as you can go before hitting Ireland, we met Preseli Venture chief instructor Jon Kellie.

Top pro Jon, aged 29, knows the sensational Pembrokeshire coast like the back of his oar.

And it was truly oarsome as we wriggled into wetsuits, squeezed into kayaks and paddled out to sea.

But the big adrenaline rush came after lunch as we swapped wetsuits, strapped on buoyancy aids, donned helmets and went Coasteering crazy.

We must have looked like a bunch of demented Spidermen as we slipped and scrambled across lethally wet, razor-sharp rocks. But the exhilarating endorphin rush powered off the end of the scale as we were battered by raging seas which threw us around like bits of wood.

What a way to celebrate my 50th.