The iconic Table Mountain, rolling vineyards and stunning ocean vistas are among the attractions that draw tourists to Cape Town, South Africa's second-largest city on its south-western coast.

But increasingly, visitors want to see another side of this contradictory city in an attempt to better understand a country with a violent history and one of the largest wealth gaps in the world.

Dozens of tour groups have sprung up over the past few years to fill this market, taking foreign visitors - about 1.8 million of whom descend on Cape Town each year - on "township tours."

They take the visitor to urban areas outside the city where the black population was confined until the end of the system of racial segregation known as apartheid 20 years ago.

Township life is far removed from the upmarket boutiques and hip cafes of Cape Town's city centre. Few white South Africans ever venture there. Opinion is mixed regarding these kind of tours, which have sprung up in a number of places including Brazil's favelas and Kenya's slums.

Critics dub them voyeuristic "poverty porn" - a chance for tourists to gawp at the lives of South Africa's poor through the windows of a tour bus and to take snaps of barefooted children playing soccer against the backdrop of makeshift shacks.

"That is why we changed the way we do things," explains Nathi, who hails from Langa, one of South Africa's oldest townships. He and his business partner have set up a tour group called Siviwe that conducts daily walking tours.

"We walk and talk to people. We don't just drive through in a car and take pictures," he adds. As Nathi sees it, such tours bring employment to the townships with tourists buying African crafts and sometimes even staying in the bed and breakfast lodgings that have sprung up. He adds that the tours also aid the cause of integration and improving race relations.

"In the 1980s, the only whites people saw in townships were police and soldiers," but now black children know they have nothing to fear from white visitors, says Nathi.

"Nowadays we are seeing more and more white South Africans doing these tours," Nathi's business partner Chipo adds. In Cape Town, which has one of the highest crime rates in the world, many white South Africans, and the growing black middle class, live in exclusive suburbs behind high walls and alarm systems.

"I feel the white South Africans are shocked to see the situation" in the townships, Chipo says.

"But the most interesting (thing) is that they are shocked how the blacks in the townships are friendly to them, so it's very positive."

Walking through Langa - a sprawling township with a population of about 52,000 - the tour takes visitors to a local pottery workshop, an experience partly designed to encourage tourists to purchase a bowl or two. Against the backdrop of a cloud-topped table mountain in the distance, the muddy roads of Langa are a bustle of activity.

Hair salons in tin shacks offer a large array of weaves, relaxers and dreadlocks. Children play soccer and hop-scotch in the street. Outside a local shebeen, or beer hall, a crowd of men are engrossed in a game of dominoes.

Women wrapped in brightly coloured traditional African skirts boil bloodied sheep heads - a delicacy in Xhosa cooking known as smileys - on smoky outdoor wood fires.

The tour takes visitors into the shebeen, a simple corrugated iron hut, where they get to sample a strong home-brewed beer known as umqombothi. Asked how he feels about foreigners descending on his local pub, Lennox, 40, a security guard dressed in overalls and a woolly beanie, says he does not see it as an invasion of his privacy.

"It's a good idea you're coming to see it," he said, before offering a shy young American tourist 100 cows in exchange for her hand in marriage - much to the mirth of the other shebeen regulars.

The tour also shows tourists the different types of housing in the township. In what Nathi wryly calls Langa's "Beverly Hills," the lower middle class have built neat brick houses, with small yards and satellite dishes on the roofs.

There are also the RDP (reconstruction and development programme) houses, a government initiative which over the past 20 years has seen millions of homes built for people living in informal settlements.

But the most basic type of accommodation are shacks, which often house large families. Portable toilets stand outside. Abbie, a 27-year-old engineer from Texas, says she initially had qualms about a township visit, but felt it had actually made her trip to South Africa more well-rounded.

"For the past few days, I've seen so much of the beauty of Cape Town, but there's so much strife and history here and you [should not] forget it," she said. But as another member of the tour stops to take the typical township shot of a little boy playing soccer, it becomes clear that not everyone is quite so hospitable. The boy scowls and gives her the finger.