It’s been what you might call a wettish start to the summer holidays. And it’s not just you who’s feeling the strain – a nation’s offspring are crawling up the walls.

Britain’s national parks are the answer, because, no matter how bad it looks outside, they offer a more waterproof weekend away. They’re stuffed with adventures both indoors and out – from theme parks to farms, show caves to railway rides, wildlife safaris to, yep, watersports.

This is National Parks Week, and “Britain’s breathing spaces”, as our 14 parks describe themselves, have organised a ferment of all-weather family-type activities. We’ve put together a comprehensive guide to five of the family-friendliest parks, from Exmoor to the Cairngorms: what to see and where to stay. Get out and get exploring – whatever the weather.

New Forest

JUST A few miles down the M3 from London, Britain’s newest and smallest national park is also one of its busiest, but pedal, trot or trudge round its 150-odd miles of car-free, pony-littered trails, and you’ll find ancient, enchanted pockets that can’t have changed a jot since William the Conqueror turned the forest into a private game reserve in 1079.

If the weather is favourable, the best place to pick up a bike is Brockenhurst, which is centrally located for circular day rides via pubs to Blackwater Arboretum (9-15 miles) or Beaulieu and the stunning 18th-century shipbuilding village of Bucklers Hard (12-17 miles). Two cycle-hire shops right at the station – Country Lanes (01590 622627, www.countrylanes.co.uk) and Cyclexperience (01590 623407, www.cyclex.co.uk) – offer a day’s hire for £13 (children’s bikes £6, trailers £7).

Also at Brockenhurst, using some of the 3,000 New Forest ponies that wander the park, Ford Farm Stables (01590 623043, www.nfed.co.uk/fordfarm) has 30-minute hacks through the forest for £15pp.

With all that magical, medieval forest, the park’s 12-mile coastline between Hurst Castle and Calshot Castle is often overlooked, but the Solent here is a (usually) sunny slice of watersports heaven. Offering windsurfing, canoeing and sailing, as well as a 45ft climbing wall and a dry ski slope, Calshot Activities Centre (023 8089 2077, www.calshot.com) is your best bet.

Families with kids in need of distraction will enjoy Liberty’s Reptile & Raptor Centre (01425 476487, www.libertyscentre.co.uk; daily, 10am-5pm; £6.50, children £4.95), which has covered facilities, and Exbury Gardens (023 8089 1203, www.exbury.co.uk; daily, 10am-5.30pm; £7.50, children aged 3-15 £1.50), which has a Wizard of Oz-themed maize maze and a steam railway (£3) around the 200-acre landscaped estate, whatever the weather. Mention Chitty Chitty Bang Bang and the Lotus/submarine from The Spy Who Loved Me, both on display this summer at the National Motor Museum, in Beaulieu, and you might even coax your offspring round the accompanying gardens, palace house and abbey ruins (01590 612345, www.beaulieu. co.uk; daily, 10am-6pm; £16.25, children aged 13-17 £9.25, 5-12s £8.25).

Family-friendly digs: the Lord Bute Hotel (01425 278884, www.lordbute.co.uk), handily placed between the national park and the coast at Christchurch, is smart but likes children; doubles from £98, family suite £135. In the forest itself, Red Shoot Camping Park (01425 473789, www.redshoot-campingpark.co.uk; £5.90pp per night, plus pitch charge of up to £3; children aged 5-14 £3.75, under5s £1.25) has a playground, bike hire and the Red Shoot Inn, all just a short walk from your tent.

For National Parks Week: Life on the Bog walk from Holmsley Lodge today (10am-noon; ages 8 and up; free). Next Sunday, explore Hurst Spit with a ranger (10am-2pm; ages 8 and up; free). Call 01590 646600.

More information: 023 8028 2269, www.thenewforest.co.uk

Exmoor

TRUE, the rugged heart of the national park feels like proper wilderness – its cutesy villages (Selworthy, Dunster) and cheery visitor attractions (Combe Martin Wildlife and Dinosaur Park, Tropiquaria Animal and Adventure Park) tend to be confined to the fringes of the moor. But you and your kids can really get to grips with nature here.

Don’t just coo over those dinky Exmoor ponies from your car: climb on board for a half-day hack across picturesque Winsford Hill, starting from the newly opened Exmoor Pony Centre (01398 323093, www.exmoorponies.co.uk; £35). You may end up beside the ancient clapper bridge at Tarr Steps, where local mythology has it that Satan goes sunbathing (but probably not in this weather).

Don’t just catch the distant holler of a stag hanging on the breeze: track the largest herd of red deer in England on an off-road Land Rover adventure with Barle Valley Safaris (01643 851386, www. exmoorwildlifesafaris.co.uk; £22/£18).

And don’t settle for spotting kestrels and harriers quartering the skies: feel their talons on a hawk walk or flying demo at Exmoor Falconry, in Allerford (01643 862816, www.exmoorfalconry.co.uk; £35).

Thanks to the ministrations of the nationalpark people, otters are resettling in Tarka country. You might glimpse one on a stroll along the sylvan riverside from the National Trust tea gardens at Watersmeet (01598 753348, www.nationaltrust.org.uk), which has a children’s quiz trail, or perhaps on a ride on the Tarka Trail to Pinkery Pond, west out of Simonsbath – get a bike at Barnstaple Junction (01271 324202, www.tarkabikes.co.uk; full day’s hire £10, children £7, trailers £8).

If your offspring would rather be splashing about themselves, the revamped watersports centre at Wimbleball Lake, near Dulverton, is a banker (they’re going to get wet anyway, so the weather’s irrelevant). It does taster sessions – dinghies, canoes, rowing boats and windsurfers – and there’s a kids’ club on Saturday for children aged 8-16 (01398 371460, www.swlakestrust.org.uk).

For littler ones, sand castles and surf are within striking range – at Minehead and Woolacombe – and there are assorted creatures of the imagination to gawp at, from a world of gnomes at Watermouth Castle theme park (01271 867474, www.watermouthcastle. com; £10.50/£9) to roaring T-Rexes at Combe Martin Wildlife and Dinosaur Park (01271 882486, www. dinosaur-park.com; £12/£7).

Family-friendly digs: Stockleigh Lodge (01643 831500, www.stockleighexford.freeserve.co.uk; £27.50pp, B&B; reduced rates for children sharing), at Exford, is a country-house B&B with wooded grounds and stables: the owners will lay on guided rides. Helpful Holidays (01647 434063, www.helpfulholidays. com) has a smattering of high-summer cottage rentals. Cloud Farm (01598 741234, www.doonevalleyholidays. co.uk) has cottages and camping (£7pp per night).

For National Parks Week: rock-pool safaris at Lynmouth tomorrow and August 6 (£1); and a search with a ranger on Wednesday (7pm, £3). Call 01398 323665 for details.

More information: 01398 323841, www.exmoor-nationalpark.gov.uk or www.visit-exmoor.co.uk.

Brecon Beacons

FOR FAMILIES with even half-fit kids, you’d be mad not to dust down your Brashers and join the Gore-Tex brigades in the Brecons. Satisfyingly mountainy yet reassuringly small, they are nourishingly rugged, child-friendly versions of the peaks in Snowdonia.

The best walk in the park for families is to the fabulous summits of the Brecon Beacons, where Corn Du (2,864ft) and Pen Y Fan (2,907ft) are well within two or three snail’s-pace hours of the Storey Arms car park, seven miles south of Brecon on the A470. Mighty views, a wonderful sense of height and some brilliant rock pools on your way down if you follow the footpath south along Blaen Taf Fawr back to the road. Rangers will lead a vast variety of walks throughout the park this summer (see below for details).

For more serious outdoor challenges (ages 8 and up), Black Mountain Activities (01497 847897, www. blackmountain.co.uk) has kayaking and rafting on the upper stretches of the Wye, climbing in Morlais quarry and biking in the Brecons; from £39 for a half-day. At Cantref Adventure Farm (01874 665223, www.cantref.com), there’s an all-weather 330ft dry-sledge slope – Europe’s longest – an indoor play zone and riding (20 minutes for £6.50, children aged 4 and up; full-day hacking up into the Brecon Beacons, £43, ages 11 and up). Cantref is open daily, 10.30am-5.30pm; £6.50, children aged 3-16 £4.95, under3s free.

As for younger children, nothing on God’s nationalpark earth will please them more than a ride on the Brecon Mountain Railway (01685 722988, www.breconmountainrailway.co.uk £9, children aged 3-16 £4.50, under3s free); unless, that is, it’s Dan-yr-Ogof National Showcaves Centre, near Abercraf (01639 730284, www.showcaves.co.uk; daily, 10am-3pm; £10.50, children aged 4-16 £6.50, under4s free), where, in addition to three vast caves, you’ll find a dinosaur park, a reconstruction of an Iron Age village and a farm with llamas, alpacas and Shetland ponies.

Family-friendly digs: the AA’s Welsh camp site of the year 2007, Brynich Caravan Park (01874 623325, www. brynich.co.uk), near Brecon, has views of Pen Y Fan and Corn Du, an adventure playground (across a brook) and a play barn for under11s. Pitches cost £16 for two adults and a car (children aged 4-16 £4, under4s free). Halfway between Swansea and Brecon, CraigyNos Castle (01639 730205, www.craigynoscastle. com), set in 11 acres of grounds, has archery, table football and pool; family rooms sleeping 5-8 start at £130, B&B.

For National Parks Week: the visitor centre at Libanus (01874 623366) has self-guided trails on Monday and Friday (£3 deposit), a Go Wild event on Tuesday (10.30am-12.30pm; ages 7 and up; £2), and a clay/paint workshop on Thursday (10.30am-12.30pm; £3.50). CraigyNos visitor centre (01639 730395) has self-guided trails on Monday and Friday (50p), Aliens Invade on Tuesday (2pm-4pm, ages 5 and up; £2) and Art Attack on Thursday (2pm-4pm, ages 4 and up; £3).

More information: 01874 624437, www.breconbeacons. org .

Peak District

YES, it has its share of tinkling streams, shaggy sheep pasture and rock-spiked moorland, but no other national park packs in so much man-made adventure, presumably because it’s the rambling back garden for several cities: Birmingham, Sheffield, Manchester and more.

The park even comes age-graded. Think of the gentle White Peak, to the south, as key-stage-one country, with ski-style gondolas zipping up to the Heights of Abraham (01629 582365, www.heightsofabraham. co.uk; £10, children £7.50), a fantasy land of catacombs and nature trails on the 1,000ft ceiling of the Derwent Valley.

And there’s Chatsworth House (01245 565300, www.chatsworth.org; prices vary), which has always offered mazes to get lost in and cascades to paddle through, but recently added fresh-born foals in its farmyard and a “children’s treasure trail” through the jewelled apartments.

To the north lies the Dark Peak, where the territory is sterner, built for older kids. The YHA’s Edale Activity Centre (0870 770 5808, www.yha.org.uk) offers family courses on which you kayak down boiling rivers and abseil off moody crags.

For a quick hit of landscape drama, tunnel down into one of the show caves around Castleton. Speedwell (01433 620512, www.speedwellcavern.co.uk; £7.25, children £5.25) wins for spookiness – you descend 105 steps into a flooded passage for a boat ride into the Bottomless Pit, echoing with spectral wails and tales of squashed miners.

Linking south with north are 30 miles of cycling trails along reassuringly flat railway-track beds – the Parsley Hay Cycle Centre (01298 84493, www.peakdistrict.gov.uk/cycle) is at the hub of the wheel, and offers bike hire (half-day £11, children £8), baby seats, toddler trailers and tandems.

Need an energy boost? The Peak District has two trademark treats for teatime: the famous Ashbourne gingerbread (from Birds bakery, 26 St John Street), and the still more famous Bakewell pudding (from the teashop on the Square). They sure beat Kendal mint cake.

Family-friendly digs: the Chatsworth estate (01246 565379, www.chatsworth.org) has holiday cottages, with decent availability this summer. Beechenhill Farm (01335 310274, www.beechenhill.co.uk) has B&B and cottage options (£32pp, children cheaper), and a farm trail.

The Palace (0870 168 8833, www.paramount-hotels.co.uk), in Buxton, is good for families, with rooms for four from £229 for two nights.

For National Parks Week: assorted ranger rambles for both long and little legs, including a torchlit trek through Dovedale tomorrow at 7.30pm and a Family Fun Walk and picnic at Tideswell on Tuesday at 11am. Call 01298 871869.

More information: 01629 816200, www.peakdistrict.org.

Cairngorms

CAIRNGORMS National Park, Britain’s largest, is a mecca for junior action junkies.

The hills are a must – Britain at its rugged, untamed best. Ben Macdui (4,294ft) is the bad boy for eager teens; Lochnagar corrie, on the Balmoral Estate, is a stunning taste of Highland magic even the average five-year-old can enjoy. For the super-slack, there’s a funicular railway (10am-4.30pm; £8.95, under17s £5.65) that takes you to within 500ft of the summit of Cairn Gorm (4,082ft). For details of guided walks from base station to summit (£5, children free), and two midnight meteorite watches (August 11-12, 9pm-1.30am), contact Cairngorm Mountain (01479 861261, www.cairngormmountain.co.uk).

Badaguish outdoor centre, near Aviemore (01479 861285, www.badaguish.org), has mountain-biking, canoeing, kayaking, orienteering and climbing (half-days and full days), with prices starting at £12pp per activity.

For wildlife, a walk or cycle on the 30-mile network of paths at Rothiemurchus (01479 812345, www.rothiemurchus.net) can turn up capercaillie and deer; a dusk hide (£20, under16s £10; children aged 8 and up) almost guarantees badgers and pine martens, while the estate fisheries (from £12.50 per hour, including tuition and equipment) are among the best places in Scotland to see ospreys.

Family-friendly digs: with 10 acres of grounds, the elegant but welcoming Muckrach Lodge (01479 851257, www.muckrach.com) has family suites (sleeping four) from £180, B&B. Cairngorm Lodge Youth Hostel (0870 004 1137, www.syha.org.uk) is a magnificent shooting lodge with family rooms (sleeping five or six) from £55.

For National Parks Week: the Rothiemurchus Estate (details as above) has a dragonfly and butterfly walk on Tuesday; Glenmore visitor centre (01479 861220), near Aviemore, has a Wild Woods Mystery Hunt on Wednesday (10.30am-12.30pm) and beach sculptures at Loch Morlich on Thursday (all day).

More information: 01479 873535, www.cairngorms.co.uk .

For details of all National Parks Week events, visit www.nationalparks.gov.uk/visiting/nationalparksweek

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