The bridge's namesake, Colonel Frederick Mears, was chairman and chief engineer of the Alaska Engineering Commission, the railroad's builder and original operator.

The bridge was the final link in the railroad, entering service in February 1923, a year after the rest of the 470 miles (760 km) line was finished.

When completed, this 700-foot-long (210 m) Pennsylvania through-truss bridge was the longest truss span in the United States and its territories.

As of 1999[update] it was then the third-longest simple truss bridge in North America.

It was one of Harding's last public appearances, as he died 18 days later during his ongoing western tour.