Pulga Bridges, Railway and road bridges in Butte County, California.

The Pulga Bridges are two stacked crossings of the North Fork Feather River: a single-track railroad truss bridge from 1909, 137 m long with spans of 34, 68 and 34 m, and above it a steel arch highway bridge finished in 1932, whose 107 m arch carries two lanes of State Route 70 about 50 m above mean high water.

The railroad bridge was completed in 1909 by the Western Pacific Railroad to create a gentle route across the Sierra Nevada. The highway bridge followed in 1932 and extended transportation connections for the newly developed State Route 70.

The Pulga Bridges Loop is listed among Plumas County's "7 Wonders of the Railroad World", although the bridges stand in Butte County. Access is described in the county's travel guide, and the site draws railfans who watch trains on the Feather River Route.

Access is via State Route 70, which runs directly over the highway bridge and offers good vantage points for viewing. The site is best visited during daylight when lighting and shadow conditions make the structures clear.

The highway bridge was built with reverse curves and a twisting superelevation, creating unusual geometry for this structure. This design was necessary to manage the steeper grade changes of the terrain while maintaining safe driving conditions.