New flights are about to make the Dominican Republic more accessible – and visitors will be dazzled by the diversity of this Caribbean gem

Sammy Davis Junior is a friend of mine. I met him last week in the Dominican Republic. He poured me Santo-libre cocktails while balancing on the tailgate of a fast-moving truck. Santo-libres are the rum-and-Sprite cousin of the more familiar rum-and-Coke Cuba-libre. They taste just as good. I had not expected to find Sammy Davis Junior alive, well, and extreme-bartending in the Dominican Republic, but I knew precious little about the country before I set off, so much of it surprised me.

It surprised Christopher Columbus, too. He knew nothing of the island when he landed on it in 1492. Nobody did. Except, that is, the indigenous Tainos, whose ancestors had called the place home for some 4,500 years. Christopher Columbus put a stop to that. He declared it Hispaniola ("little Spain") and, with one eye on future colonisation commissions (and marketing brochures), noted in his journal that it was "a beautiful island paradise with high forested mountains and large river valleys". Then he set about ruling the New World. HQ: paradise.

Nowadays, Hispaniola is made up of two countries. The troubled nation of Haiti takes up one-third of it, to the west. The more relaxed Dominican Republic comprises the two-thirds to the east. Both countries have about nine million inhabitants, making the island by far the most populous in the Caribbean (nearly twice as many people as neighbouring Cuba). Big swathes of it seemed pretty empty to me. That's because it is also – after Cuba – the second biggest Caribbean island. The Dominican Republic alone has a coastline about 1,000 miles long, and the country has both the highest peak in the Caribbean (Pico Duarte, at 10,161ft) and its biggest lake (Lake Enriquillo, which spans 102 square miles). Sammy Davis Junior filled me in on all of these facts, and many more, all the while mixing cocktails bottle-to-bottle as our truck hop-skipped over dirt-track ruts.

As one of Outback Safaris' longest serving guides, Sammy has been telling tourists what's what for 18 years. He has a well honed patter. ("I'm Sammy. Like Sammy Davis Junior. Look, my face looks like Sammy Davis Junior's.") But most British visitors to the Dominican Republic haven't been listening. Until now, the majority have been package tourists on charter flights to all-inclusive resorts. But from Monday, British Airways will start flying to the Dominican Republic twice a week, paving the way for more independent-minded travellers to visit and explore.

There's a lot to see. I began (after a day-and-a-half of laborious non-direct flights from the UK) in the capital, Santo Domingo. It was pouring. Slug-fat raindrops hammered the car on my way in from the airport. Gutter-spouts lining the tiled rooftops in the Zona Colonial fire-hosed the cobbled streets. Then, as we approached the Basílica Catedral Santa María de la Encarnación, the rain stopped and the sun came out. This was the first cathedral in the New World. The first hospital is round the corner, as is the first monastery, the first university, and – less marketably – the first slave-trading port.

Winston Marrero, a Dominican born and raised in Santo Domingo, showed me the colonial city with obvious pride. He pointed out the nine arches on the cathedral's Parque Colón façade, no two of which are the same, and the palm tree motif of the vaulted ceiling. Molten light poured into the cathedral from three sides hung with vast, open doors. Winston explained that each door weighed 1.5 tons, and that they swung on their original, five-hundred-year-old hinges. Then he showed me how he could move one with a fingertip, before ushering me outside into the heat.

"It's hot," I said, squinting. Winston agreed, and bought me a hat. Stunned by this generosity, I thanked him and licked my lips, whereupon he bought me a beer. I'm wary of generalising about national traits, but I am honour-bound to mention that this same hospitality was common to every Dominican I met. People I'd barely met invited me to friends' birthday parties. They say crime rates are low, that it's safe for travellers, and that "the people make the island". I've never been anywhere so friendly.

We drank our beer – a Dominican Presidente – in the beautiful tiled courtyard of the Hostal Nicolas de Ovando, overlooking the Rio Ozama. My Presidente was served in a glass so cold that the first inch of beer I poured froze on contact with it. I waited to pour the rest, considering the bright red bougainvillea which – as throughout the colonial city – tumbled over the courtyard walls.

The flowers were almost as vivid as the tropical fish I swam with off Punta Cana later, at the Marinarium Marine Park. I took the Reef Explorer tour. It comprises a boat ride out to a big pontoon which floats above a protected coral reef. Snorkelling equipment, kayaks and fruit punch are all thrown in, as are a series of pens containing large but harmless stingrays and nurse sharks. You can swim with them, see them fed, even touch them – all of which is impressive, if zoo-like. For me the chance to float off among the wild needlefish, angelfish, trumpetfish, spotted-scorpionfish, and peacock flounders, all themselves weaving psychedelically in and out of the sea fans and knobby sea-rods, was better still. (Helpfully, there's an identification chart on the floating island.)

Punta Cana is the eastern tip of the Dominican Republic. It's where the new British Airways flights from Gatwick will land. It's also where most of the big, all-inclusive resorts are, and some smaller, more luxurious hotels. By "smaller" I don't mean small, and by "big" I mean massive: there are about 36,000 rooms spread among the hotels here, some of which have up to a thousand suites. The biggest hotels lurk among sprawling golf courses at the end of long drives, sheltered behind corporate-looking gates. They're largely American- and Spanish-owned, they're big business, and they're not, on the face of it, particularly Dominican.

That said, they're a great place for a holiday. I stayed a night in Dreams Punta Cana. The sea here is Photoshop turquoise, the sand is sifted white flour, palm trees sprout along the beach at picturesque angles. My "Preferred" suite had two bathrooms, two sinks, two televisions, and enough towels to dry a football team. Once I'd fought through the pillows to the bed, the pile on the floor was as tall as me. The resort has seven restaurants and 10 bars, and a wiggly-edged pool the size of, I don't know, Hyde Park. And everything, from dinner to windsurfing, is, when you've paid up front, free! Even the drinks. I tested this freeness out, while taking a stroll, navigating by way of the helpful, if literal, hotel map. Hearts on it are designated "romantic spots". I checked one out, but – perhaps because it was low season – there was nothing happening.

The Dreams Resorts (there's another one an hour away in La Romana), though big and luxurious, are neither huge nor lavish by local standards. The Sanctuary at nearby Cap Cana is posher still. It has suites with private plunge-infinity-pools, and there are golf courses at Cap Cana designed by Jack Nicklaus, and Donald Trump has something to do with the place, and ... you get the picture. There are no all-inclusive deals at the Sanctuary. Total luxury, it seems, incorporates the pleasure of reminding yourself you're rich by paying as you go.

These hotels weren't here 40 years ago. Not much was, just verdant hills tumbling into white beaches stabbed full of coconut trees. For some reason this landscape, and the neon blue sea, and prevailing breeze, seemed attractive to Frank Rainieri, Punta Cana's first hotelier. With US investment, he gave the area everything from its first real road, to its airport, even its name. Everyone else has essentially piggy-backed off the success of the Punta Cana Resort, which now comprises a number of hotels, including its flagship, Tortuga Bay.

The interesting thing about the Punta Cana Resort for me wasn't Tortuga Bay's understated opulence and exquisite cuisine, so much as the story of how the hotel came to be where it is, and the resort's place in the wider scheme of things. Luxury is often synonymous with waste, yet from the outset Grupo Punto Cana has fought to yoke refinement to sustainability, making the most of the environment without spoiling it.

As Jake Kheel, head of the company's Ecological Foundation (formed in 1988), explained: "We're not just talking sensible towel laundering." From the outset nothing on the property has been built taller than a coconut tree. The resort's water is recycled for use on its golf courses, which are turfed with salt-tolerant grass grown in soil produced from the hotels' recycled kitchen waste, itself chomped to usefulness by resident Californian Red Wriggler Worms. All this is real: Jake showed me the worms.

He also explained the Foundation's Rhinoceros Iguana conservation project (they're inveigling them on to the golf courses), and its plan to reintroduce the Ridgway's Hawk to the area (there are thought to be only 120 breeding pairs in the wild). Beyond these environmental initiatives, the Punta Cana Resort has built two schools and a hospital, and recycles the airport's waste as well as its own. If guests tire of the award-wining spa, silky sand, and world-class golf courses on offer, they can involve themselves in many ways. As Jake pointed out: "Folk donate time, supplies or cash to our projects, and from December they'll be able to help the resident ornithologist count birds, too."

Having discussed wildlife with Jake, I was relieved that the deep sea fishing I'd planned was to pursue mahi-mahi, a plentiful, edible catch. Gone Fishing of Puerto Plata supplied the boat, Sarabel, and guidance (Emmanuel); the deep blue sea provided the nine mahi-mahi I managed to land. Yup, nine. Nobody was more surprised than me.

Having baited my hooks after Emmanuel's patient ("let's try again") instructions, and bobbed around for an hour or so catching nothing but the sun, the scratchy scream of the first reel igniting bounced me from my seat. Mahi-mahi swim in shoals. Another reel began shrieking, then a third. The fish on the end of my line leapt higher and flashed greener and were simply much larger than any I'd ever caught before. Emmanuel was kind enough to let me do the hard work (sorry, reeling) so that he could concentrate on laughing at my companion's shrieks.

They're strong fish. By the end of the day I had shredded hands to go with my red neck. The catch, incidentally, goes to the crew of the boat, who sell it to local restaurants. My grin was the widest but I wasn't the only one smiling. The largest fish I landed weighed 20lb, and the portion of mahi-mahi I ate in the excellent Jellyfish restaurant the following day cost US$20 (£13).

Saona Island is also at this eastern end of the Dominican Republic, an hour or so south of Punta Cana. I wanted to go there because I'd read it was where they filmed those Bounty bar adverts from the 1980s. And it's exactly like the advert, with sand so bleached-white and sea so ridiculously turquoise you can actually taste the paradise. But just in case you can't, you can lop down a coconut, machete off its top, and drink the milk. I did this as well, albeit with the help of a professional Saona Island coconut chopper: the long-distance-lopping is more fiddly than it looks.

And more dangerous, too. Dominican road etiquette is, well, quixotic, with helmet-less families, four to a motorbike, vying for space among the potholes with pickups and buses, and one-way signs that it's apparently OK to ignore. I'd be surprised if there were not a fair few nasty accidents a year. But Sammy Davis Junior (he did actually look very much like Sammy Davis Junior) who taught me many things about the country, swore blind that more people are killed in the Dominican Republic by falling coconuts than they are on the roads. He also told me that coconut oil, taken in differing doses, cures both diarrhoea and constipation, stops hair losing its colour, and helps prevent heart attacks. Having barely scratched the surface of his stunningly beautiful country, I choose to believe what Sammy Davis Junior told me about it, because Sammy Davis Junior is a friend of mine.

Travel essentials: Dominican Republic

Getting there

* British Airways (0844 493 0787; ) launches a new twice weekly service from Gatwick to Punta Cana via Antigua on Monday. Returns start at £642.80. The writer flew with BA to Antigua and with Liat (001 268 480 5601; ) on to the Dominican Republic.

* BA (0844 493 0758; ) offers seven nights at the four-star Dreams La Romana Resort in Punta Cana from £753 per person (or at the five-star Dreams Palm Beach from £884 per person) departing in November. The price includes return flights from Gatwick and all inclusive accommodation, based on two sharing. Book by 31 October. Seven nights at the five-star Tortuga Bay in Punta Cana starts at £2,447 per person departing in January, including return flights from Gatwick, return VIP airport transfers and accommodation with breakfast, based on two sharing.

Staying there

* Tortuga Bay, Puntacana Resort & Club, Punta Cana, Higüey (001 809 959 2262; ).

* Dreams Palm Beach Punta Cana, Cabeza de Toro, Provincia La Altagracia, Higüey (001 866 237 3267; ).

* Dreams La Romana, Playa Bayahibe, La Romana (001 809 221 8880; ).

Visiting there

* Amstar DMC, Carretera Bávaro, Km 2, Amstar Business Center, Punta Cana (001 809 221 6626; ) runs excursions and tours. The writer took tours to Saona Island, the Marinarium Marine Park and Aquarium, deep-sea fishing and an outback safari.

More information

* Visitors require a tourist card, which can be obtained before travel from the Embassy of the Dominican Republic for £10, or on arrival at the airport for US$10 (£6.60). If you intend to stay for up to two weeks departure tax is US$20 (£13.20). Scheduled airlines sometimes include this in the price of the ticket. If you intend to stay for more than two weeks, departure tax varies depending on length of stay and on nationality.

Dominican Republic Tourist Board: 020-7242 7778;