Rio's expecting visitors, and she's become house-proud

I'm a pushover for a pretty city. Mountains, ocean, ivory beaches and pristine rainforest make Rio de Janeiro the most drop-dead gorgeous location in the world.

Cariocas complete the seduction with samba, bossa nova, carnival, and football. Even the streets names are bathed in glamour and glory – Copacabana, Ipanema, Corcovado, Maracana. It's enough to make anyone giddy, but I am not alone in falling for Rio. Fifa was also bewitched – the 2014 World Cup finals will be here and now the IOC has gone weak at the knees. Welcome to Olympic City 2016.

Rio still has its dark side. The murder rate is staggering, at more than 2,000 last year, mostly due to drug wars in the notorious favelas. But Cariocas will be hoping to transform this image before the Olympics. The makeover was already under way when the city hosted the Pan American Games in 2007. The showcase beaches of Copacabana, Leblon and Ipanema certainly look cosmetically improved. The wave-patterned mosaic pavement on Copacabana, by the landscape architect Roberto Burle Marx, looks newer and cleaner, the sand is immaculately manicured and illegal vendors and street kids seem to have been hustled away from the main drags. And no litter. Rio no longer takes its blessings for granted. It has become house-proud.

Some of the favelas, which can look deceptively picturesque from a distance, have undergone beautification – one of the shanties is painted cobalt blue in an optimistic rebranding. But, no matter how squalid the conditions, a room with a view seems to be the birthright of all Cariocas. As the favelas cling to the steeper edges of Rio's hills, it is true that the poorest residents of Rio enjoy some of its better views.

The most spectacular view, though, requires a little distance. The Tijuca National Park is the world's biggest urban forest. It is a remarkable early green initiative laid out by King Pedro II in 1861. Worried that sugar and coffee planting was causing soil erosion and water shortages in the city, he ordered the reforestation of the 8,000-acre estate. The actual back-breaking re-seeding of the jungle fell to slaves – just 11 of them. They did an amazing job and, 150 years on, it's impossible to imagine this teeming forest could ever have been anything but a place where wild things roam.

The panorama from the Chinese Pavilion (a landmark in the park) is every postcard of Rio brought to life. The spine of the Tijuca ridge kicks up to Corcovado mountain, topped by the landmark statue of Christ the Redeemer. The clouds dance around the statue threatening to claim him completely. His outstretched arms embrace the districts of Botafogo and Flamengo below. Further away, the distinctive hump of Sugar Loaf mountain pokes out of the sea.

It is a wrench to leave Rio, even for a day. But, in the spirit of duty, I make two excursions. The first is to another national park, Itatiaia – about 150 miles away – a four-hour drive along the main highway to São Paulo. It doesn't help that, as the car turns inland, the sun remains parked over the receding coastline and ahead is a blanket of grey.

0The national park is the oldest in Brazil (set up in 1937), and boasts the country's third-highest mountain, Pico das Agulhas Negras (9,400ft). But as the car turns off the main road and clatters upwards on a rough track, less and less of the park is visible. It is not called Cloud Forest without reason.

From about 5,500ft, I cannot shake off the impression that I have taken a wrong turn and left the tropics. At around 7,500ft the track ends and I set off on foot in a cloud of greasy atomised rain that insinuates itself between cagoule and thermals and should have its spiritual home in the Hebrides.

The park boasts 250 species of bird – many of them DayGlo plumed – but today they hunker down out of sight. Two hummingbirds do appear, darting around like turbo-charged Tinkerbells while I shelter from a downpour at a park ranger's hut. The rain intensifies and the gloom thickens. The austere granite ridges and the threatening sky offer no hint that I am in the land of samba. I could be in Scotland; Scotland with hummingbirds.

The second excursion is happier. Angra dos Reis is a more accessible 60 miles west of Rio. The coastal road to the town is clean and undeveloped with stunning views of mountains, ocean, and little sheltered bays. It seems unfair that so much natural beauty should be so casually strewn around. And then the Bay of Angra itself appears and trumps the lot.

Sheltered from the whiplash moods of the Atlantic by the breakwater island of Ilha Grande (the aptly named Big Island is 120 miles long), the bay is spotted with 365 other islands and no less than 2,000 beaches. It is, unsurprisingly, a playground for Rio's super-rich and privileged classes. The media baron Roberto Marinho, who many would say was the real power in Brazil until his death in 2003, had a beach home here. The biggest private island in the bay, Ilha dos Porcos Grande (Big Pig Island), still belongs to the cosmetic surgery entrepreneur Ivo Pitanguy, who had an airstrip hacked from the rainforest to facilitate his comings and goings.

There is a festive air in Angra. Hundreds of day-trippers from Rio are here to enjoy the lovely day – worth celebrating as the town's micro-climate tends towards rain. Angra was an important port, its history tainted by the slave trade, that now makes a living as the jumping-off point for the bay. Frigate birds glide on their sharp boomerang wings over the colonial buildings. A jumble of dense tiered houses clings precariously to the hillside beyond, their once vivid salmon pink, duck-egg blue and orange hues beaten down by the weather and sea salt.

Out in the bay, my pleasure boat chugs past Marinho's beachfront – the house seems surprisingly modest for a man whose means and tastes might be expected to lean more toward Citizen Kane-ish folly. We stop for a swim off an islet opposite and, immediately, the translucent waters are teeming with happy, frolicking Cariocas. The water is so clean as to seem insubstantial. Everything on its surface – bathers, inflatable toys, boats – seem weightless.

We stop for lunch on the island of Gipoia. I am told that the Jurubaiba and Flechas beaches on the island are very popular, but there is little sign of development. Next to the jetty, whitewashed tin-roofed fishermen's cottages occupy the strip of sand between water and dense forest. There are no souvenir shops or jangling bars. Yet, this dozy tropical idyll is only an hour and a half's drive from the metropolis with its six million inhabitants.

When I return to Rio the shock of the city is amplified by the Metropolitan cathedral of São Sebastião. It is a spaceship of a building, a 315ft high upturned concrete cone that would not have looked out of place in Steven Spielberg's Close Encounters of the Third Kind. Designed by the architect Edgar de Oliveira de Fonseca, it is a monumental piece of work, brutal on the outside but, from inside, the perforated walls and the four rectilinear stained-glass compositions create a soaring momentum leading the eye to a huge cross-shaped skylight. The effect is just as crushing and awe-inspiring as any Gothic pile in olde Europe.

In architectural terms, the recently opened Hotel Santa Teresa is the exact opposite. It uses materials such as coconut fibre, sustainable tropical wood, cotton and linen to affirm a human scale in touch with the natural world. The triple-height reception space has a wonderful poise and calm. The local artefacts and folk art have been chosen to maintain a warm, intimate feel. And there is a cheeky wit at work; a row of callipygous bums sculpted from polished hardwoods winks at the Brazilian obsession with the bunda.

Upstairs, the view from my balcony is relatively low key by Rio de Janeiro's standards. There are no landmarks of note to see, but from here I can take the pulse of life in the neighbourhood; dogs bark, children play, a motorbike is being revved up and the dramatic surge of music from a telenovella drifts up the hill on the warm evening air. Out in the distance, on the Baia de Guanabara, little pinpricks of light are moving across the bridge to Niteroi.

It is another snapshot of an irresistible city. But why resist? World Cups, Olympic Games. What Rio wants, Rio gets.

Compact Facts

How to get there

Sankha Guha flew to Brazil with TAM Airlines (tamairlines.com), which offers return tickets to Rio from £548. He stayed at the Hotel Santa Teresa (santateresahotel .com), which offers superior rooms from £240 per night.

Further Information

Brazil Tourism (braziltour.com).