On top of creation

Normally, only parrots and toucans get an overview of the rainforest of Central America. Simon Calder joined them

Who the heck put that there? Anyone who has skied in the Alps will recognise the equipment. Yes, it is at altitude (about a mile high), and the base station lies in a valley. But the setting for this open-sided gondola is unlike any cable car you have ever seen. Instead of soaring above blanched mountainsides, it floats over Central America, a leaf's whisper above the rainforest canopy.

When I first heard about an "aerial tram", strung over the highlands of Costa Rica, I was horrified. How can anyone get away with plonking a gawking great piece of Alpine machinery in the middle of the country that has done more than almost any other to preserve its natural order?

Quite easily, it turns out. From the capital, San Jose, you approach the location on the road across the continental divide to the Atlantic port of Limn. This is a typical Costa Rican highway, which means its characteristics are (a) savage swerves, (b) unfeasible gradients and (c) a wildly three-dimensional surface straight out of the Somme.

Wherever your gaze turns, it seems to be filled with an improbable amount of scenery: great brutes of rock impassively look down upon the timidity of man's endeavours, while patches of ultra-green jungle are highlighted by the tropical sun, then suddenly subdued when a cloud bumbles past.

Below you, especially on the bends that resemble the hairiest of pins, those gaping voids look ready to swallow up anything that moves an inch too far beyond the highway.

So it is something of a relief to stumble upon a cake shop.

A short way off the highway is a huddle of timber lodges that comprise base station for the Mesa Verde cable car. The restaurant at the centre sells all sorts of food, but a restorative slab of sponge and shot of coffee is what you need to bolster your nerves, here between the devil of a Costa Rican highway and the deep green sea of rainforest. Now you are ready to explore the settlement, and to discover that what could, from a distance, be taken to be a logging camp serves exactly the opposite purpose.

You find yourself being educated about the rainforest, and the creation of a theme park where the motif is nature, in a beguilingly unscholarly manner. This pre-flight briefing tees you up nicely for a preciously intense experience. With a bit of ungainly clanking, the gondola creaks aloft to a world that is humdrum to the hundreds of species of bird that make Costa Rica their home, but which few humans ever see: life in the treetops, on top of creation.

The ride lopes, rather than swoops, across the valley, swaying gently in time with the birdsong. This is terrain, you are told, that is in rejuvenation after a fire raged through it. Nature does that, which is why anyone desperate to preserve primary rainforest will have to put up with the trees - and those creatures that snuggle symbiotically within their embrace - being periodically reduced to ashes. You could be floating across the millionth version of this extraordinarily renewable resource.

Awe: not the call of a macaw, but the main emotion when you are confronted by the natural scheme of things. Close to the top, only the most energetic young buds emerge, and this sparse, magically translucent carpet allows you to peer through to the stout trunks of tropical hardwoods. Lower down, the branches knit increasingly closely with a web of ambitious creepers and waifish ferns.

The spectrum narrows to a flush of greens, which reaches its darkest conclusion when it merges with earth the colour and texture of treacle. To expand the colour range, just look up: the Costa Rican sky always seems to be ripped in a spat between blissful blue and baleful clouds whose mean darkness increases proportionately with the intensity of the sun sneaking through the gaps.

A non-violent U-turn (this is a cable car, not a Costa Rican bus) ushers you back the way you came, but so adroit is the concealment of the base- camp cluster that you are on your final descent before you see the 20th century approaching and shaking you roughly from your dream flight. This time, the cake tastes even sweeter.

You will have worked out that cable cars require a series of supports. How can this be achieved without devastating the forest floor? With difficulty. Donald Perry, the American behind the project, hired a helicopter from the Sandanista army of neighbouring Nicaragua to drop the pylons in.Environmental purists can make a sound case against the venture - not least on the grounds that it will encourage tourists to fly thousands of miles to hover above the rainforest. Yet if ever there were a means of creating instant affection for this fragile planet, the cable car achieves it.

Affection accompanies you throughout a trip to Costa Rica. I'm even fond of the squabble of unofficial currency dealers that greets new arrivals at San Jose airport, resembling a battalion of bandidos. Though these fellows look even shiftier than the immigration officials, you soon realise you are unlikely to be robbed either by them or their poorer, more desperate compatriots in the ragged quarters of San Jose.

You know those places where you feel instantly at home, even though you are thousands of miles from domesticity? The capital of Costa Rica is like that. The main street is a riotous shambles, but dart down any side street to devour a stack of tortilla and you will make friends, if not for life then at least for as long as it takes to gulp down a beer.

Every visitor gravitates to El Pueblo, an entertainment complex on the (relatively) affluent north side of town. Imagine a mock-colonial village infiltrated by some swaggeringly good restaurants, and you have a place which feels a bit like the set from an Hispanic soap opera. It's tremendous fun: when San Jose flutters its civic eyelashes and pouts, you can almost believe you're in Buenos Aires.

The more you look around, the more you suspect you are the only member of the audience to have accrued your wealth by entirely legitimate means. With luck, a Bolivian band will bring a rarefied Andean repertoire for the benefit of a well-heeled clientele. The shrill panpipes will resonate with tuneful gasps that tempt you deeper into Latin America. That happened the first time I came here, and within a year I was gasping through La Paz. But I keep coming back to Costa Rica, to partake of a commodity that both the people and the land share in abundance: good nature.

Simon Calder bought his flights through South American Experience (0171- 976 5511), flying to Miami on Virgin Atlantic, and onwards to San Jose on American Airlines. The best price at present for this route is pounds 455 return, including tax.