China's transport economy posted steady growth in the first seven months of this year, with freight volumes, passenger flows and port throughput all increasing, while investment in infrastructure remained high, the Ministry of Transport said Wednesday.

From January to July, the country moved about 33 billion metric tons of freight, up nearly 4 percent from a year earlier. Ports handled more than 10 billion tons of cargo and around 200 million containers. Passenger flows reached close to 40 billion trips, while total investment in the transport sector came to nearly 2 trillion yuan ($280 billion).

In July, when the annual summer travel season began, both passenger and freight transport picked up. Freight volumes rose modestly, while air cargo expanded by double digits. Passenger trips increased as families traveled for holidays and students returned home, with railway journeys leading the growth.

Ports also reported stronger performance in July, with total cargo throughput climbing nearly 7 percent year-on-year and container traffic edging higher.

Investment continued to support expansion, with more than 300 billion yuan poured into transport projects in July, most of it in highways and railways.