More than 17 million vehicle trips have been made on the Nairobi Expressway since it opened to public a year ago, according to its operation company.

On average, every working day more than 60,000 vehicles run on the expressway - the first toll way in the East African country - a significant increase over the initial period of its operation, said Moja Expressway Company.

Electronic Toll Collection has become the dominant payment method for its users, with 75 percent of fee payment now made using ETC, compared with 27 percent one year ago, the company said.

The expressway, built by China Road and Bridge Corporation, spans 27.1 kilometers and connects the urban area of Nairobi with Jomo Kenyatta International Airport, the main airport of Nairobi, and reduces travel time between the city center and the airport to 20 minutes from around two hours.

In the first half of the year, delegations from other African countries including Tanzania, Zambia and Nigeria visited the expressway, and expressed interest to study the successful experiences in the management of the expressway so they can be used in their own countries, said Steve Zhao, CEO of Moja Expressway Company.

As a major infrastructure project in the East African country, Nairobi Expressway, which was opened to service on July 31 last year, has greatly eased traffic congestion in the capital Nairobi and injected vitality to the country's economic development.