CHISHI, China — Soaring over a lush valley in southern China, the Chishi Bridge is a 1.4-mile-long marvel of concrete and steel. Four piers, like graceful tuning forks as tall as skyscrapers, secure cables suspending a four-lane expressway 610 feet above fields of corn and rice.

Squinting up from a dirt road below, Gu Tianyong, a 66-year-old farmer, pondered the colossus, which is a shortcut linking southwestern China with the east coast.

“The government wouldn’t have built it if it was useless,” he said. “It does nothing for me, but must be useful for the country.”

The Chishi Bridge is one of hundreds of dazzling bridges erected across the country in recent years. Chinese officials celebrate them as proof that they can roll out infrastructure bigger, better and higher than any other country can. China now boasts the world’s highest bridge, the longest bridge, the highest rail trestle and a host of other superlatives, often besting its own efforts.