Tourist films his wife in underground river and accidentally creates a mind-boggling visual effect… but can you tell how he did it?

TOP STORIES IN TRAVEL

• Out of this world: The best commercial flights for witnessing the total solar eclipse over the Pacific Ocean
• Dropped in the ocean: Shocking moment million-dollar yacht plunges into the water after a crane harness snaps
• Life with the lion whisperer: Incredible pictures show the bond between a man and his pride of big cats
• Lies, thieving and sex in the skies: Cabin crew reveal what they REALLY get up to during a flight in shocking survey
• Guests defecating in the pool and being robbed at gun point: Hotel front desk managers reveal their most shocking experiences
• Living RIGHT on the edge: Stomach-churning pictures show Russian daredevils dangling off the country's tallest buildings... with no harnesses
• Is this REALLY the most comfortable way to sleep on a plane? New travel pillow where you bury your face in the cushion
• The ultimate desert playground: Model of Dubai's $2.8billion theme park extravaganza with 100 attractions is unveiled
• How much would YOU pay for a caffeine fix on holiday? The price of a Starbucks latte in 30 countries revealed (and you'll need deep pockets if you're off to Zurich)
• Co-pilot forced to land passenger plane after captain suffered massive heart attack and died mid-flight
• The world's worst (and best) airlines revealed: EasyJet and Virgin Atlantic rank at bottom of study that scored carriers on quality, flight delays and compensation
• Revealed: The best airports in the world for a flight layover (and none are in the UK or US)
• Fancy staying somewhere rubbish? The solar powered pods for beachgoers to sleep in overnight that are made from plastic dumped in the ocean 
• How much would YOU pay for a caffeine fix on holiday? The price of a Starbucks latte in 30 countries revealed (and you'll need deep pockets if you're off to Zurich)
• Put your shoes in shower caps and hide your money in sanitary towels: The smartest ways to reuse household items while travelling
• Water parks, unlimited ice cream and a 13,454-square-foot play area: The best hotels in the world for families revealed in TripAdvisor's traveller awards
• Hundreds of passengers arrive at their destinations without their luggage after airport sorting device REFUSES to work because it didn't recognise the leap year
• A cosy Devon eco-lodge, glam Lake Como hotel and a grand Swiss 'medical master' resort: The world's best spas revealed
• Investigation launched after two Israeli fighter jets came within just THREE miles of packed Ryanair flight
• Is this Airbnb's worst listing EVER? Rental site features a double bed in an outdoor car park in London for £8 a night
• Former RAF pilot calls for tests to show results of drones hitting passenger jets that could result in 'uncontrolled engine failure or a smashed cockpit windscreen'
• Take a tour of London's dark side: The interactive map that reveals the chilling sites of the capital's public executions
• Who knew toothpaste could mend a cracked screen? The ultimate hacks for fixing smartphone problems on holiday 
• Nature's masterpieces: Incredible images reveal the stunning beauty of braided rivers that look like inky watercolour paintings
• Former RAF pilot urges £250K tests to show results of drone hitting passenger jets which could result in 'uncontrolled engine failure or a smashed cockpit windscreen'
• The film selection had better be good! 'World's longest flight' from Dubai to New Zealand lands in Auckland after 17 hours and 15 minutes in the air 
• The stuff Dreamliners are made of: Stunning timelapse video reveals how a brand new 787-9 is built from scratch
• You may now... kiss someone other than the bride! Men are TWICE as likely to cheat than women on a stag or hen party
• How shellfish! Passenger attempts to carry a LIVE lobster worth $500 in his luggage through a Chinese airport (but the creature is seized and incinerated)
• Icelandic budget airline names hot pink plane TF-GAY in support of LGBT rights
• If a tree falls in a forest... you won't hear it over this daredevil's screams! Thrillseeker captures heart-pumping footage of a wild zip line ride in the Philippines
• 'Parisian shopkeepers laughed in my face': Travellers reveal what they kept SECRET about their holidays on their return
• 'The maddest road ever': Terrifying footage shows the moment tourists attempt to avoid a 2,000ft drop as they steer a van around a VERY narrow track in Nepal
• Businessman banned from flying after 'flipping' on a plane: Traveller put his pregnant wife in a headlock and PUNCHED her on packed holiday flight 
• Long before the days of snowboards, helmets and crowded slopes: Fascinating vintage photos reveal the glory days of ski holidays
• No wonder he looks so happy: Expert on travelling for free does it again, flying from New York to Melbourne in business class... without spending a single penny
• 'Is the snow cold at my ski resort?' Travel agents reveal the most amusing or bizarre questions they've ever been asked by holidaymakers
• From chalet girl to chalet guest, an avid skier returns to Val d'Isere ten years on and finds there's more to the resort than just good food and flirting
• Fancy owning a hotel in paradise? Caribbean beachside resort with a pool, restaurant and spa could be yours (but you'll need to splash out $6.8million)
• Tourist films his wife in underground river and accidentally creates a mind-boggling visual effect... but can you tell how he did it?
• Pictured: The incredible 190ft bronze model of a Chinese war hero that's five times heavier than the Statue of Liberty
• Designer wardrobes, private submarine tours and a personal Nobu chef: The extravagant perks holidaymakers can get for FREE
• 'I thought we would die, this is the end:' Passenger's horror after looking out of the window to see engine 'spewing fire' as plane makes emergency landing in France
• Why in-flight wifi isn't as safe as you think: Passenger's emails hacked by fellow traveller while using exposed connection
• The enduring appeal of a Sixties classic: Why a new generation ispacking up the campervan and heading out on the road
• Dreaming away the day on Zanzibar: Coral reefs, colonial history and chic cuisine on Tanzania's grand slice of ocean paradise
• Broken bones, skinned arms and open wounds: Stranded holiday couple plead for £15,000 to get home from Vietnam after horrific Valentine's Day motorcycle smash
• 'Head, armpits, crotch and toes': Hilarious new video aims to teach spa hygiene etiquette to confused visitors to Iceland
• We carrot wait for this! The world's first bunny spa is coming to London with free treatments and roaming rescue rabbits
• Taking the high road over the border: Cosy inns, good food and aching legs on a hike from Spain to France through the Pyrenees
• Passengers evacuated from plane after fireworks discovered in back of seat 'brought on by a group of school children'
• 'You didn't strike it rich here in Vegas, but you did hit the jackpot': The heartwarming moment a man is told he is going to be a father during pilot announcement at 35,000ft
• Every day is a winding road: How a vintage campervan is the perfect way to explore hippy Isle of Wight
• And the award for best internet meme goes to... New pre-flight safety video spoofs the Oscars with appearances by doge, a double rainbow and a screaming goat
• The best of Bangkok: Fashion, food and fun - why the capital of Thailand is more than just a stopover on the journey to the beach
• Are you taking the Leap? Forget the fly and flop, the ultimate new honeymoon destinations for once-in-a-lifetime adventures revealed
• The world's most powerful passports revealed (and the UK and US both slip from the top spot)
• Snub skis and ice skates for spas and five-star luxury: A winter wimp's guide to putting on the St Moritz
• From the Beach Boys to The Beatles: A road trip around California's classic locations made famous by album covers and legendary rock exploits
• Inside China's 'ghost cities': Photographer captures country's massive urban developments... without an inhabitant in sight
• Security fears at Stansted after 6ft3 bearded bouncer managed to board a Ryanair flight to Dortmund using the passport of his 5ft 2in girlfriend 
• Having a ball with Viv's dream team: Why Antigua is so much more than just a tropical paradise 
• Whale, hello there! Photographer captures the incredible moment an open-mouthed humpback whale breaches water
• A 24 hour escape to the country: Ockenden Manor provides the perfect antidote to city life with its natural spring spa and Michelin-starred restaurant .
• Not just a pipe dream! Mum-of-three, 57, travels 50,000 miles to play the bagpipes in all seven continents
• Where to go for that cycling break: Norfolk... or Rwanda? Saddle up for a mesmerising trek to see the African country's famous mountain gorillas
• Amazon, Andes and Aguas Calientes: How to see the best of Peru while immersed in its culture and natural wonders
• All aboard the Carnival Breeze: This is the most fun you'll ever have in the Caribbean 
• Now's the perfect time to marvel at the master of Milan
• Feeling on top of the world on Bear Mountain 
• Luscious ice wines, sticky maple syrup and a marshmallow to top it off: Why Niagara is the sweetest place on Earth .
• Great food, top-notch childcare and plenty of activities on tap: Lemnos is a winning break for sporty families
• Playful orangutans, active volcanoes and acidic-green crater lakes: How Sumatra's dangers are also part of its appeal
• An Italian masterpiece: No trip to Florence is complete without a viewing of Sandro Botticelli's work at the Uffizi gallery
• Fantastic pistes, a sunken jacuzzi and plenty of cheese: Chamonix will have any keen skier wishing they had gone sooner 
• Romance of the rivers: River cruising has never been more popular, so which one is best for you?
• An Inspector Calls: The Bel & The Dragon's new Kingsclere hotel takes hospitality to new heights
• Travel notes: What's new and how to get the best from your holiday 
• Low-cost airlines mark up in-flight snacks including cup-a-soup by up to '2,600 per cent' study claims
• Heartbreaking photos reveal the charred remains of iconic Californian shipwreck loved by locals and tourists alike
• On board the happiest flight on Earth: New Disney-themed Boeing 767 is unveiled with cabin crew in costume and passengers served Mickey Mouse meals
• Terrifying moment onlookers shout in horror as ominous shadow of a gigantic shark swims just feet away from a lone kayaker
• Passenger went hungry for over 24 hours after Air New Zealand FORGOT to pack her gluten free meal (despite her forking out $5000 for flight)
• Student nurse sues Ryanair after a bottle fell from overhead locker and hit her in the face - leaving her with a 'slight scar' on her nose (and forcing her to cancel her 40th birthday party)
• Plane forced to divert to Sarajevo and five drunk passengers arrested after they stole alcohol from the service trolley and abused cabin crew
• Would YOU holiday in a war zone? Daredevil Brit is addicted to backpacking in the world's most dangerous countries including Sudan, Syria and Iraq (braving gunfire, kidnap and interrogation)
• Outbreak of BED BUGS on British Airways flight from the U.S. to London
• Malaysian Airlines plane bound for London forced to turn back to Kuala Lumpur after engine problem and 'strange smell' in the cabin
• Wish YOUR holiday looked like this? The ultimate travel Instagram accounts to follow for intense wanderlust
• Rising from the ashes: The first ever Boeing 727 set to take to the skies once more... after sitting in a museum for 25 years
• 'Can you turn off the wildfire smoke?' Locals who live in holiday destinations reveal the most ridiculous questions tourists ask them
• Passenger sues Royal Caribbean after he was 'flung nearly 18 feet against his cabin door and knocked UNCONSCIOUS' during stormy Anthem of the Seas cruise
• Going, going, almost gone? The 900-year-old Scottish castle built by King William in danger of sliding down a 100ft cliff into the sea after being battered by recent storms
• EasyJet to resume flights to Sharm el-Sheikh in May if government lifts travel ban enforced since Russian airliner bombing
• Is this the world's most luxurious hotel? Inside the Baroque-inspired palace that cost £1 BILLION and comes with retractable marble floors, Rolls-Royce Phantoms for guests and a butler for every room .
• Furious mother slams 'cruel' airline after it refuses to warn other passengers of her daughter's severe nut allergy (leaving her to pay thousands for flights home with a different carrier)
• Now THAT'S a family heirloom: Inside the world's oldest hotel that's been passed down 52 generations in its 1,311 year history (and it's still attracting guests thanks to its natural hot springs)
• Drunk flyer who attacked passengers and cabin crew is the latest 'airline hooligan' to be arrested on flight to Iceland
• Would YOU like to spend the night in a shed? From a WWII bunker to a converted boat, Britain's weird and wonderful micro accommodation to rent on Airbnb
• The aviation race is on! Carriers compete to offer the world's longest, non-stop flight... and it's Singapore Airlines' mammoth 19-hour trek that is lined up to take the title
• A bird's-eye view of the 'ghost town' of the Mediterranean: Drone footage shows decaying hotels and land reclaimed by nature at Cyprus resort once visited by Elizabeth Taylor and Brigitte Bardot
• Fancy being king of your own castle? Scottish pile with 53 acres of grounds, including a world famous garden could be yours for £5million (and you might even see a ghost!)