China is to invest about 77 billion yuan ($11.7 billion) this year on the construction of civil aviation infrastructure, especially airports, according to the Civil Aviation Administration of China.

The agency said it will step up construction of important new airports, including those in Beijing, Chengdu, Qingdao, Xiamen and Dalian.

Eleven key infrastructure projects and 52 upgrades or expansion work on civil aviation facilities will be started this year, the administration said in a statement.

It said work on Beijing’s second international airport, the largest construction project in Chinese civil aviation history, is progressing well.

Work on the terminal and air traffic control facilities began in September and construction of support facilities is expected to start in June.

The airport is scheduled to be completed in June 2019 and to become operational in December that year, the administration said.

The civil aviation agency will also work with the National Development and Reform Commission, the country’s top economic planner, to publish a blueprint this year on the locations of new civil airports to be built before 2030, according to the statement.

Dong Zhiyi, a deputy director at the administration, has said China plans to build 66 new civil airports in the next five years, taking the number of such airports on the Chinese mainland to 272 from 206.

Demand has been rising for air travel, spurring the development of more airports.

According to the National Tourism Administration, Chinese travelers made more than 4 billion trips to domestic destinations last year. They also made 120 million trips abroad, an increase of 16 percent year-on-year.

The civil aviation administration said Chinese made 440 million trips by air last year and predicted that the figure could rise to 485 million this year.

Jiang Yiyi, director of the China Tourism Academy’s International Tourism Development Institute, expects more than 130 million outbound trips to be made by Chinese this year, a year-on-year rise of 10 percent.

To satisfy the increasing demand for overseas trips, in addition to building new airports, the administration plans to sharply increase the number of international air routes in China.

The Civil Aviation Administration of China will help domestic and foreign airlines to open more than 200 new international routes this year, its director Li Jiaxiang said.