Beijing plans to start a trial operation of late-night subway services, aimed at helping people arriving on the last high-speed trains of the day get to their final destinations, a senior official said recently.

On Thursday, World Car Free Day, Zhang Jiandong, deputy mayor of Beijing, and Zhou Zhengyu, head of the Beijing Municipal Commission of Transport, handed out information on "green transport" to citizens, encouraging reduced car usage.

Zhou said during the event that Line 4, the north-south line that serves Beijing South Railway Station, will begin a trial of late-night services.

At present, the last subway train leaves the railway station at 11:15 pm.

Travelers arriving at the station later than that will be able to take the subway to other parts of the city, Zhou said, without giving a specific timetable.

Beijing's subway lines total 554 km. Zhou said the city plans to increase the distance to 900 km by 2020, which would mean that Beijing's subway system would be longer than New York City's and London's combined.

"This will help to ease congestion," Zhou said.

Beijing has seen an increase in visitors to the city, and traffic congestion has become a bigger problem, he said.

Meanwhile, those taking flights from Beijing Capital International Airport will be able to check in their luggage at the Dongzhimen transportation hub, where passengers can take the subway to the airport.

Han Jiayuan, a frequent commuter at a trading company in Beijing, said it will be much easier for her because she always has to carry heavy luggage.

New York City operates 24-hour subway lines, while London's subway is open until 1 am. London is testing 24-hour lines. Tokyo's subway runs until 1 am, while Seoul's operates past midnight.

While most people are likely to support late-night subway services in Beijing, some have questioned whether it is an efficient use of public resources.