Above Isla Bolanos, a small rocky outcrop in the sea off north-west Costa Rica, magnificent frigatebirds wheel in wide circles; closer to ground level, their adolescent offspring make short excited flaps across the nesting ground. And in the bay behind them, a single, brightly coloured wing swoops and dives, lifting a lone figure through the air with marvellous height and speed. Da Vinci would weep at man's easy, dextrous flight, if only he had the chance to observe the kite surfing at Bahia Salinas.
Costa Rica is a compelling juxtaposition of volcanoes and rainforest, azure sea and powder sand. It is known as a surfer's paradise, but relatively little known as a kiting destination. Perhaps this is because its singular geography – on the isthmus joining North and South America – makes the bay at Bahia Salinas the only place to kite surf on the western coast of Central America.
But this bay is perfect. The winds rise on Lake Nicaragua; they are then funnelled through a small gap in the mountains of the Cordillera Central, and towards Bahia Salinas; the curve of the coast means that this strong, constant wind blows onshore, making it safe to kite.
Shaggy blond Italian Nicola Bertoldi was one of the pioneers of kite surfing in Costa Rica. He discovered the area in 2000 when the road – still unsurfaced today – was a dirt track, and spent solitary months teaching himself. "Most of the time I wasn't even in the water," he laughs. "I was always untangling my lines." Now an expert, he is bringing his experience to bear as an instructor, "so other people can avoid making my mistakes".
For those who've not seen it, kite surfing is the lovechild of wind surfing and wake boarding, without the awkward mast/sail combination of the former, or fuel-guzzling engine needed for the latter. It has its roots in 13th-century China, but was reinvented in the 1980s by wind surfers in Hawaii and France. It's currently one of the fastest-growing watersports, with some 250,000 practitioners around the world.
After watching Nico's balletic aerial performance, my own attempts are clumsy beyond measure. But I'd learnt the basics, so after a brief safety drill Nico suggests I give it a whirl. First he hands me a pair of booties, explaining: "You know – in case you step on a stingray."
The water is delicious, some 25C. I slide my feet into the straps on the board and move my kite across the "wind window" (the imaginary arc above my head from nine o'clock to three o'clock) to start – and immediately, ignominiously, face-plant. No question, I'm still a hatchling, faltering in erratic bursts. Striding along the shore, issuing directions into the walkie talkie tied to my helmet, Nico offers corrections and encouragement.
Much like skiing, learning to kite is exhausting. And deeply uncool. Each time I bellyflop into the water I loose my board. I must "body drag", putting the kite low in the sky and tacking upwind using my body as a rudder, to try to find it. Body dragging is a good way to swallow spectacular quantities of saltwater. One hunt is particularly difficult: every time I spot the fin, it moves. At last, I realise what I am chasing is not my board, but a green turtle.
However, the pain of hours spent thrashing and cursing is erased by the joy of a few minutes riding. On the odd occasion when it works, the wind fills my kite, my sinews strain to throw my weight back in the harness as I rise up, and then sing through the water, jumping the rough toss of the balmy waves.
The dry season, from November to April, sees winds building to 25-30 knots, which blow constantly from sunrise to sunset. Unlike more prominent kite destinations, such as the Caribbean Cabarete or Spain's Tarifa where crashes are a common hazard, this beach is rarely crowded. "The most I've ever counted in the air at one time is 22," says Nico, cracking open an Imperial beer at the end of the day.
Nico also runs the Blue Dream Hotel, whose 14 simple bedrooms are cut into the hill above the bay, each with views across to Nicaragua. Any guests not spending the day on the beach can idle in the spa, practice on the yoga terrace, or sea kayak for half an hour to Isla Bolanos. It is a pleasant distance, which I make in the company of two brown pelicans. After dragging the kayak onto the crescent sand, I scramble to the top of the island, and silently stand watching the magnificent frigatebirds feed their young; this is one of only two of their nesting colonies in the region.
Costa Rica is one of the few places in the world where you can surf as well as kite. So I took a break from the Blue Dream Hotel, drove south to Playa Coco and hired a boat to take me to the notorious two-mile shore break at Roca Bruja, or Witch's Rock. The great chunk of stone was once part of a volcano, and was thrown here in a monumental eruption. The break, glorified in surfing circles by the seminal movie The Endless Summer 2, was swelling to a majestic barrel. From the relative safety of the deck, I watched experts disappear into the belly of the waves and emerge euphoric seconds later.
On the way back, I detoured inland, leaving the arid, baking heat of the coast as I zigzagged up the cool, green hills around the active Arenal volcano. Here, the climate becomes temperate. The 33km lake beneath the volcano is flanked with retirement homes for Americans and Europeans, and the Alpine feel is enhanced by cuckoo-clock chalets and a surprising number of German bakeries. Lake Arenal is also possible for kite surfing, but the water is colder, and the molten colours of Arenal's lava flow are obscured by ash, so I choose to return and spend my last day back at Bahia Salinas.
As the tide goes out, the glassy water reflects the pink of the sky. I carve upwind, one lazy hand trailing in the water, ebullient. Nico sails past and reaches out for a high five; he goes on to jump, suspended in the air for six, seven seconds, before landing with a flourish, his spray golden in the low light.
Da Vinci believed that "When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return." I share the sentiment for kite surfing in this remote corner of Costa Rica.
* The closest international airport to Bahia Salinas is Liberia. Thomson Airways (0871 231 4787; thomsonfly.com) flies weekly from Gatwick, although this service will be withdrawn on 30 April. The best way to get to the Bahia Salinas is by taxi, which costs around $75 (£50) for the 75-minute drive.
Costa Rica's main international airport is at San José, four-and-a-half hours' drive away. There are no direct flights from the UK. The US is the main connecting country, or you can travel via Madrid or Mexico City.
Local buses connect San José to La Cruz for around $8; a taxi from there to the hotel costs $14 for the 15-minute journey.
Kite surfing there
* Blue Dream Hotel, Playa Papaturro, Bahia Salinas, La Cruz, Guanacaste, Costa Rica (00 506 2676 1042; bluedreamhotel.com). Doubles from $25 excluding breakfast. Private kite surfing lessons cost $40 per hour, including equipment.