Wang Chuangcu is a veteran train driver with 20 years of experience. He gained a certificate to drive bullet trains in 2009 and has safely driven 1.75 million kilometers on over 3,500 trips.

"I used to climb up and down the Qinling Mountains, but now I drive through them in tunnels," he said.

The Xi'an-Chengdu high-speed railway, which opened on Dec 6, is the first high-speed line traversing the Qinling Mountains in Shaanxi province. Tunnels, which allow the train to pass through the mountains, reduce disturbance to wildlife.

"The old generation of locomotives had weaker engines and the old line is one of the most complicated railways in the world. Sometimes it required two or three locomotives to help a train cross the mountain. As a driver, I had to concentrate every minute," he said.

Wang started test runs along the Xi'an-Chengdu high-speed railway in July and has noticed the benefits of the tunnels and bridges.

"I don't need to make countless turns or drive up or down hills, but pass through the tunnels and arrive at the destinations," he said.

The slow train takes about 11 hours from Xi'an in Shaanxi to Chengdu in Sichuan province. The new train will take about 4 hours.

When Wang first started working, he drove trains at 60 kilometers per hour. Now he drives a train that can reach 250 km/h.

"Although it passes through tunnels, the bullet train on the new line is very smooth," he said.

He attributed the improvement to the high-quality construction standards of the new bullet trains.

The new type of bullet train, the CRH 3A, has a wider body, increasing stability when making turns, he said.