Adventure holidays don't have to cost a fortune. In fact, some of the best family adventures we've had have cost almost nothing at all - a bodyboard, a packed lunch, and a beach with good waves. The key is knowing where to look and not assuming that adventure means expensive.

We've done everything from climbing mountains in Wales and camping in the Gower to bodyboarding in Cornwall and exploring Merlin's Cave at Tintagel. Most of it was cheap or completely free. Here's how to plan an adventure holiday for your family without spending a lot.

Choose a destination with natural adventure built in

The best value adventure holidays happen in places where the landscape itself is the activity. Coastlines, national parks, and areas of outstanding natural beauty give you endless free things to do - walking, climbing, swimming, exploring - without paying for entry to anything.

We live in Newquay in Cornwall now, and the adventure available on our doorstep every single day is extraordinary. Coastal walks along the South West Coast Path, bodyboarding at Watergate Bay, rockpooling at low tide, sand dune sliding at Holywell Bay, seal spotting at Polly Joke - all of it completely free. If you're visiting Cornwall for a family adventure holiday, the coast will keep you busy for an entire week without spending anything beyond parking and a pasty. If you're planning a visit, 10 things to do on your family break to Cornwall is worth a read for ideas beyond the beach.

Wales is another brilliant choice. We spent time exploring the Gower Peninsula by campervan, camping at Rhossili Bay and waking up to one of the most dramatic beaches in the UK. We've also done the famous four waterfalls walk in the Brecon Beacons - one of the best hikes we've ever done as a family, where you can actually walk behind one of the waterfalls. You don't need to spend anything beyond fuel and a sandwich to have a day like that.

Camping or glamping keeps costs down dramatically

Accommodation is usually the biggest cost of any holiday. Camping brings it right down and, more often than not, makes the whole thing feel more like an adventure anyway. Kids love camping. Waking up next to a beach or in a field in the middle of a national park is a genuinely exciting experience for them.

We've camped in the Gower, in Devon at Branscombe Airfield, and taken the campervan to various spots around the coast. Even a basic tent and a well-located campsite costs a fraction of what a hotel or cottage would. There are plenty of ways to save money when you go camping too, from bringing your own food to choosing sites just outside peak areas.

Glamping is a nice middle ground if you want something more comfortable - it's more expensive than camping but usually far cheaper than self-catering cottages or hotels, and the setting tends to be somewhere genuinely beautiful.

Fill your days with free activities

The adventure activities that cost the most money - theme parks, activity centres, quad biking and the like - are great for the occasional treat, but they don't need to be the backbone of an adventure holiday. If you drive a quad or try paid adventure activities, factor it in as a treat rather than a daily expense.

Some of our favourite free family adventures:

Bodyboarding - you need a bodyboard and a beach with waves. That's it. It's worth paying a bit more for a decent quality one rather than the cheap polystyrene boards you see in seaside shops - those snap and break easily and you'll end up replacing them. A proper bodyboard costs around £30-50 and will last for years. We bodyboard at Watergate Bay in Cornwall regularly. The kids have learned to read waves and time their runs and they absolutely love it. There's also free wooden bodyboard hire available at various surf shops in Newquay and across Cornwall if you don't want to buy your own.

Coastal walks - the South West Coast Path alone offers hundreds of miles of free walking with extraordinary scenery. We've done sections including Newquay to Perranporth, Daymer Bay to Rock, Watergate Bay to Mawgan Porth, Mother Ivey's Bay to Constantine Bay, and Holywell Bay to Polly Joke. Pack a picnic, download an offline map, and you have a full day out for nothing.

Exploring caves, rock pools and beaches - Merlin's Cave at Tintagel in Cornwall is one of the most magical places we've taken the kids - a cave that goes all the way through the headland, accessible at low tide, completely free. Rock pooling at low tide is endlessly entertaining for children and costs nothing. Sand dune sliding at Holywell Bay is another favourite - the dunes are huge and you can use an old bodyboard as a sled. Funnily enough, those cheap polystyrene boards that aren't up to the waves get a second life as perfect sand dune sleds!

Mountain walking and hiking - if you're near a national park, walking costs nothing and the views and sense of achievement are unbeatable. The Brecon Beacons four waterfalls walk is one we'd recommend to any family with children old enough to manage a decent hike. Snowdonia, the Lake District, Dartmoor - all offer free walking with real adventure built in.

Wild swimming and river dipping - not just the sea. Rivers, lakes and wild swimming spots give a different kind of adventure and are almost always free. If open sea swimming or wild swimming feels too daunting, look out for tidal pools around the coast - natural rock pools that fill with seawater at high tide and provide a much calmer, safer place to swim at low tide. They're brilliant for children and nervous swimmers, and you'll find them dotted all around the Cornish coastline and beyond.

Cycling - if you have your own bikes, look for free cycling trails wherever you're visiting. We've ridden the Camel Trail in Cornwall, which runs from Padstow to Bodmin along a traffic-free former railway line, and the free bike trails at Lanhydrock. Many national parks and forests have free or very low-cost cycling routes - Forestry England trails, canal towpaths and converted railway lines are all worth searching for in any area you're visiting. Taking your own bikes removes the cost of hire entirely.

Bring your own equipment where you can

Renting equipment adds up fast. Hiring wetsuits, bodyboards, bikes and kayaks for a family of four every day of a week's holiday can cost hundreds of pounds. If adventure activities are something your family does regularly, buying your own equipment makes sense very quickly.

We have our own bodyboards and wetsuits. We also own a couple of SUP-YAK paddle boards, which we bought ahead of moving to the coast and which have already paid for themselves many times over. If you camp regularly, your own tent, sleeping bags and kit will save money compared to glamping or renting gear every time.

Plan around free entry and off-peak timing

Many of the best adventure destinations in the UK are in or near National Trust or National Park land where entry itself is free - you're paying only for parking, and even that can be reduced or free with a National Trust membership (which pays for itself quickly if you visit regularly).

Visiting in shoulder season - late September, October, early spring - means you pay less for accommodation, campsite pitches are more available, beaches are quieter, and you often get better weather than the peak summer crowds would have you believe. There are plenty more money saving travel tips worth knowing before you book.

Don't write off a UK staycation as "not adventurous enough"

We live in Cornwall and the adventure available here genuinely rivals anything we've experienced abroad. The Atlantic waves, the dramatic cliffs, the hidden coves accessible only at low tide, the ancient caves and headlands - it feels wild and properly adventurous.

The Gower, Pembrokeshire, Snowdonia, the Jurassic Coast, the Lake District - the UK has extraordinary landscapes that deliver real adventure without the cost of flights, foreign currency or lengthy travel. For a family on a budget who want an adventure holiday, the UK is genuinely hard to beat.