At less than 12.5 miles (20km), it has a long way to go to realise Cecil Rhodes's dream of a Cape-to-Cairo railway, but at least it's a start.

The R24bn (£2.15bn) Gautrain was launched in South Africa today, just in time to carry World Cup football fans and to usher in a new dawn in the chequered history of African railways.

The Gautrain is the first high-speed urban train on the continent, capable of 100mph and hailed as an antidote to Johannesburg's notorious traffic jams.

The first route links OR Tambo international airport to Sandton, the commercial hub of Johannesburg. Like Britain's Heathrow Express, it takes about 15 minutes and is far quicker than travelling by road, but it compares favourably in price at just R100 (£8.94).

When the Guardian took a test ride of the Gautrain recently, progress was comfortable if a little cautious. The train had a sleek silver and gold exterior, but the inside was unnervingly familiar: the Electrostar carriages, built by Bombardier Transportation in Derby, are also used by various British operators. Less familiar is their cleanliness, at least for now.

What seems the epitome of mundane routine for the average British commuter is being seen as near miraculous in a city where, like Los Angeles, the car is king and the train is nowhere in sight when navigating the sprawling suburbs.

A crowd gathered at 5.24am this morning for the train's inaugural journey. One traveller, Narcizo Makwakwa, told the BBC he took the train from Sandton to the airport "just for a joy ride", adding: "After this, I am going to work but I had to see it. I couldn't wait for the past seven years for this, it is beautiful."

When it first appeared the Gautrain would not be ready, officials were quick to point out that it was never intended to be a World Cup project. But now that the first leg is able to carry fans from the airport to Sandton, where many will be staying, it seems to have become part of the euphoria engulfing the country before kick-off on Friday.

However, like the hosting of the tournament itself, there are questions over who wins and who loses from the Gautrain, which has been criticised for running behind schedule and over budget.

The fares – collected with a pre-paid smart card rather like London's Oyster card – may seem cheap by British standards but are likely to be too expensive for the majority of South Africans.

The air-conditioned train will eventually link Johannesburg, the nation's commercial capital, with Pretoria, the administrative capital 31 miles away, in a 40-minute journey.

This will be a tremendous boon to the mostly middle-class drivers who sometimes crawl in traffic for more than two hours. The Gautrain will also connect with Park Station in Johannesburg's less salubrious downtown.

But critics say this excludes the millions of poor people who live in townships such as Soweto. They are forced to rely on minibus taxis on some of the world's most dangerous roads, and metro commuter trains which have a reputation for overcrowding, muggings and cancellations due to strikes.

The transport divide reflects how geography shaped South African society under racial apartheid, with black people forced into townships on the outskirts of cities. Even today, many black workers are forced to rise before dawn and spend a high percentage of their earnings to reach their workplace.

South Africa is this month marking the 150th anniversary of the country's railways, but intercity services are now generally infrequent and little used by residents. In the age of the car and plane, the train has become almost a tourist novelty – most notably the five-star luxury Blue Train.

But for now, the launch of the Gautrain, along with state-of-the-art World Cup stadiums, is being championed as proof that South Africa is no longer travelling second class in the world. "It has created a feeling of national pride," said government minister Jeff Radebe. "South Africans can achieve the impossible when we put our minds to it."