The world’s most exciting wooden rollercoaster: that’s the claim made for Megafobia, 80 vertical feet of shrieks, rattles and rolls at Oakwood Theme Park, in Narberth. Awesome for kids — but who needs artificial highs when just a few miles south hurtles seaside Britain’s greatest thrill ride, the Pembrokeshire coast?

This is one of the all-time-great bits of seashore, packing in crags and castles, kayaking and candyfloss, and, most of all, clean, clean beaches. Last year, the county netted 11 Blue Flags and 32 Seaside Awards - Britain’s biggest haul - which means there’s a spruce strand for everyone.For tots, there is jolly Tenby, its car-free old quarter protected by three Blue Flag beaches and 20ft medieval walls. North Beach is all about cobbled alleys and cockles on the quay; South Beach has trampolines and bouncy castles. Teens may prefer Freshwater East, where a new watersports hub (01646 672764, www.tyf.com) lays on surfing, kayaking and coasteering.

For sun goddesses, it’s got to be Barafundle Bay, a far-flung crescent of moon-white sand that waxes and wanes among National Trust cliffs. For beachcombers, there is Manorbier, its rock pools crammed with cuttlefish bones and mermaid’s purses; and for romantics, Lydstep Caverns, all caves and blowholes, with winkles cuddling in every crevice. Then there are Pembrokeshire’s islands, packed with seal pups (Ramsey), puffins (Skomer) and perfume-making monks (Caldey).

Wherever you hole up, please don’t miss the bogglingly beautiful walk from Bosherston, with its Monet-esque lily ponds, across Broad Haven sands and along the gull-draped cliffs to St Govan’s Chapel, a tiny hermit’s chapel washed up on the shore of a deserted cove.The freshly revamped St Brides Spa Hotel, in Saundersfoot (01834 812304, www.stbridesspahotel.com; doubles from £140) offers the swishest stay here, with a marine-therapy spa and a stunning clifftop infinity pool. Giltar Grove (01834 871568, www.giltargrove.co.uk; doubles £60), at Penally, is a lovely, log-fired B&B; while the new National Trust cottages at Stackpole Quay (0870 458 4422, www.nationaltrustcottages.co.uk; from £498 per week) look like somewhere the Famous Five might take on a gang of smugglers. Spiffing! For more information, go to www.visitpembrokeshire.com

BROADSTAIRS, Kent

If Charles Dickens took his bucket and spade back to Broadstairs this summer, he’d find the beach busy with twirly moustaches and stripy bloomers, the high street bustling with bustle-wearers. June 16-24 sees the 70th annual Dickens Festival, staged in honour of the bearded wonder whose working holidays there produced David Copperfield and Nicholas Nickleby.In truth, however, the town doesn’t need fancy dress to charm the bed socks off you.

It remains England’s most beguiling old-time seaside resort, its ice-cream parlours and “milk bars” stacked spickly against the chalk cliffs behind Viking Bay, a mile-wide smile of Blue Flag sand.Nearby Whitstable attracts the Islington set, keen to frequent oyster bars and fall off kiteboards, but Broadstairs has escaped toff-friendly titivation and retains the stout family values of yesteryear. Yes, bellyboards have replaced the bathing machines, but it has an old-fashioned funfair, firework shows and an August water gala featuring swimming races and knobbly-knee contests. You’re seeking a traditional (but tat-free) seaside holiday, with donkey rides, bandstand concerts and Punch and Judy? That’s the way to do it.

If Viking Bay gets too parasol-packed for comfort, five more sandy beaches scallop out to the north, including Joss Bay, with its surf school (07812 991195, www.jossbay.co.uk). These become steadily whiter and wilder all the way to Kingsgate Bay, ideal for shrimping, fossil-hunting and cave exploration.The Royal Albion Hotel (01843 868071, www.albionbroadstairs.co.uk; doubles from £127, B&B) is a very Broadstairs place to stay: genteel and comfortable, with a terrace overlooking the harbour. The Victoria (01843 871010, www.thevictoriabroadstairs.co.uk; doubles from £88) is a chintz-free five-star B&B; or check out the Fishermen’s Cottages (01843 601996, www.fishermenscottages.co.uk), charismatic conversions that are perfect for families.

ROSS OF MULL, Inner Hebrides

St Columba landed on the Ross in AD563, and from here spread Christianity throughout the Scottish mainland — frankly, it’s a wonder he tore himself away. Fringed by bone-white beaches, washed by cobalt seas, the peninsula has a stark, ancient beauty enjoyed even today by more otters and seals than tourists.Iona, the tiny island off the Ross’s western tip where St Columba founded his abbey, draws most of the tourist heat — and with good reason. For a start, there’s the abbey itself, where St Columba, several kings of Scotland and the late Labour leader John Smith are all buried.

It is is now the spiritual headquarters of the Iona Community (0141 332 6343, www.iona.org.uk), which offers week-long ecumenical retreats from £75, full-board.Even without the abbey, the island would be worth a week for its beaches, particularly Camus Cuil an t-Saimh (“the Bay at the Back of the Ocean”), which stares forever out across the Atlantic towards America. That, along with local scallops and crab at the Argyll Hotel Iona (01681 700334, www. argyllhoteliona.co.uk; sea-view doubles from £124, B&B), is as good for your spirit as anything the abbey has to offer.

If it’s serious spiritual rebirth you require, however, then the 12 or so miles of coastline to the west of Rubha nam Braithrean offer at least 10 beaches that are unchanged since St Columba first skinny-dipped in their shallows. You’ll need walking boots to reach the best of them — the tiny, custard cove of Traigh Bhan, perhaps my favourite, is a four-mile hike from the trailhead at Ardchiavaig — but what a journey’s end. Ardachy House Hotel (01681 700505, www.ardachy.co.uk), which overlooks the one-mile beach at Ardalanish Bay, has doubles with views of Jura, Colonsay, Islay — and even Ireland — from £96, B&B.

BAMBURGH, Northumberland

Other beaches have rollercoasters — Bamburgh has one of Europe’s most dramatic castles. It’s right there on the edge of the sea, perched on a basalt crag, as if God had decided that the nation’s sand castles weren’t up to scratch, and that we all needed a proper fort to copy from. “There,” he said. “Now do you see what you should be doing?”From the ramparts, you can look in every direction and see the setting for another day’s adventure. To the north lies the harbour town of Berwick-upon-Tweed, girdled with mighty, cannon-proof walls. Holy Island is there, too, home to Lindisfarne Priory, a lonely causeway road and yet more golden sand. Immediately offshore are the puffin-friendly Farne Islands, while to the east rise the wild, high moors of the Northumberland National Park.

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