Walk in the footsteps of giants to St Michael's Mount, Marazion
Cross the causeway to a sea-encircled castle, once home to a legendary giant who was lured to his death by a brave local lad. Children love to hunt for the giant's stone heart etched in the pathway, follow clues to the castle turrets and stand in the firing line of bygone battles. The climb to the castle is too steep for buggies, but hipster seats are available (free) or you can take in the island vibe from the 18th-century village and seafront cafe. To emphasise the magic of being an island castaway, time your trip with the tides so you walk one way and ferry hop back.
• 01736 710507, stmichaelsmount.co.uk, ?7 adults/?3.50 children, family ticket ?17.50, National Trust members free (open March-November). Garden ?3.50/?1.50, open April-September, limited opening hours (see website). Castle + garden ?8.75/?4.25, family ?21.75
The UK's most southerly point offers a dramatic landscape, and sometimes a peep of a seal or a basking shark, too. But even with a Cornish ice-cream in hand, a wave-lashed promontory will distract the kids for only so long. So head for the Lizard Lighthouse Heritage Centre, where they can climb the tower, sound a foghorn, track ships and build their own lighthouse. This should fire them up to explore the surroundings, and take the coastal stroll to Lizard Point (not too taxing, but it does stray close to the cliff edge). Top it off with a trip to the village for a legendary Anne's pasty (Sunny Corner, Beacon Terrace, Helston, annspasties.co.uk) and watch local serpentine rock being turned in one of the gift shops.
• 01326 290202, trinityhouse.co.uk, entry and lighthouse tour ?6 adults/?3 children. Opening hours vary
There are enough adrenaline-packed rides at Flambards to put a smile on teenage faces. Younger visitors can take a more leisurely ride on the Cornish Mine Train and Animal Express; inquisitive minds can try the Hands On Science Experience, and if the weather pulls a face you can pile into the new indoor play zone (for 1 to 11-year-olds). All ages collide on the car track, where teenagers and toddlers race around sporting policemen's hats and butterfly wings (from the dressing-up cabin). And if it all gets too much for the grown-ups, then slink off for a moment's peace in the award-winning gardens and aviary.
• 01326 573404, flambards.co.uk, ?21.95 adults/?13.95 children (90cm-15yrs), various family-value tickets available. Open daily 31 March-2 November, times vary
You can't mention a day out in Cornwall's gardens without signposting its mega-star, the Eden Project, but there are other sub-tropical gardens which flourish naturally in the county's mild climate. At Trebah, follow children's trails under lush canopies and through colourful tunnels; check out Tarzan's Camp; paraglide through treetops and emerge on the small river beach on the Helford river. If it's warm enough go barefoot on the sand, grab an ice-cream from the Boathouse cafe and unpack a picnic; if it's drizzling, the Planters Cafe serves locally-sourced snacks.
• 01326 252200, trebahgarden.co.uk, ?8.50 adults/?2.50 children (aged 5-15), discounted winter rates November-March. Open daily from 10am to an hour before dusk
It's no surprise that this picture-perfect crescent of sand is a hit with families. Its trump card is Elemental UK water sports centre, which offers kayaking, sailing, snorkelling, stand-up paddle-boarding, windsurfing and coasteering. It also runs kids' clubs on most weekends and during school holidays from Easter through to October, so parents can opt out and flop on the beach (on cooler days, pick up a poncho and hot water bottle from the beach cafe) or head into Falmouth for some retail therapy.
• swanpoolbeach.co.uk. Elemental UK: 01326 318771, elementaluk.com, year-round activities (minimum age 6) from ?10 per hour, kids' clubs (April-October) from ?18pp for three hours, or ?30 per day
Where can children board a chopper, dress as a pilot and play a virtual lifeguard? At the NMMC, which has a 70ft Sea King helicopter on display this year – so climb aboard. As well as experiencing search and rescue heroics, children can helm radio-controlled yachts, watch harbour wildlife in the underwater gallery, celebrate Britain's Olympic sailing heritage and climb to the lookout. Round off the day by stepping into the shoes of local seafarers with a 20-minute boat trip from the Prince of Wales Pier to St Mawes, where you can visit the castle and eat pasties on the beach (buggies welcome on the ferry).
• 01326 313388, nmmc.co.uk, ?9.50 adults/?6.50 children (6-15), under-5s free; open daily 10am-5pm. Boat trip 01872 861910, falriverlinks.co.uk, adults ?8 return/children ?4.50
Hire a river boat, Mylor Creek
Children, dogs and wannabe sailors can cast off on the waterways of the Carrick Roads from Mylor Harbour, a chic little marina tucked into the mouth of Mylor Creek. With basic sailing experience under your belt you can hire a pocket cruiser; if not, putter along creeks and rivers on a motorboat. Pack binoculars (a pair per child to save bickering) to keep the kids enthralled as they look out for herons, peregrines, seals and even dolphins. Pack reins to secure wriggling babies and toddlers as you explore this boating paradise: anchor in sandy bays, go with the tide to Truro, or moor up for a riverside cuppa and cake at Tregothnan's Tea Bar (pictured).
• Mylor Boat Hire (01326 377745, mylorboathire.co.uk), boats from ?30 per hour; open April-October. Tregothnan Tea Bar, Philleigh (tregothnan.co.uk/smugglers/the-tea-bar1) open daily from Easter, midday-5pm
Frolic with fairies at Golitha Falls, Bodmin Moor
Photograph: Alamy
Cornwall's natural beauty isn't all about the seaside; veer inland to Bodmin, to explore a wilderness said to be inhabited by a mischievous fairy tribe, the Cornish piskies. Golitha Falls Nature Reserve is one such place, where footpaths (including a buggy-friendly trail) tunnel through a wooded valley alongside the tumbling river Fowey. Kids can scale tree trunks, tiptoe across stepping stones and march over bridges – there's enough to keep them happy for hours. The centre of attention – for most adults at least – is the waterfall finale as it cascades down the gorge. There are plenty of places to unpack a picnic in a fairytale glen, but come prepared – there are no facilities or refreshments en route.
• naturalengland.org.uk. Free entry, toilets in the car park
Paddle the River Tamar
Photograph: Alamy
With its medieval roots and glorious grounds sloping to a watermill on the Tamar, Cotehele (nationaltrust.org.uk) is a fantastic family day out in its own right. Better still, hop on a guided Canadian canoe trip from Cotehele's quay and delve deeper into the Cornish mining world heritage site, traced by Cornwall and Devon's watery border. Family teamwork is essential as you manoeuvre through steep-sided woodland punctuated by boatyards, mining chimneys and quays – once the heart of a thriving copper industry. Children from three upwards can hop aboard, and when they tire of paddling keep them busy looking for leaping salmon and the blue flash of kingfishers, until you moor up in a riverside meadow for a picnic break.
• Canoe Tamar (01822 833409, canoetamar.co.uk) offers return trips from Cotehele to Harewood from April-September, ?25 adults/?21 children (under-5s free). Cornish mining world heritage site: cornish-mining.org.uk
Explosive exhibitions at Wheal Martyn, near St Austell
Photograph: Alamy
Kids love seeing machinery in action – and watching giant drills blast china clay from the pit at Wheal Martyn is like a trip through Play School's round window. Explosions aside, there are attractions for the whole family. Hands-on exhibits and audio-visual displays delve into the history of Cornwall's china clay; there are activity sheets with colouring, crafts and quiz trails. Run off steam on the commando-style assault course, wander through acres of woodland (look out for deer) and visit Cornwall's largest working water wheel. Complete the authentic Cornish experience with a taste of the local produce, served in the Victorian remains of a china clay settling tank.
• Wheal Martyn China Clay Country Park (01726 850362, wheal-martyn.com), ?8.50 adults/?4.75 children (6-16), family saver ?26. Open mid January-24 December from 10am (see website for days)
Hayley Spurway lives in Hayle, St Ives Bay and writes about family activities on her blog (seainsight.co.uk)
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