Lower Blackburn Grade Bridge

The Lower Blackburn Grade Bridge is a reinforced concrete arch span crossing the Van Duzen River with distinctive inset panels decorating its surface. The structure showcases the through-arch design that defined engineering practices during the early 20th century.

John B. Leonard designed this bridge in 1925 as one of five structures built for California State Route 36 connecting Fortuna and Red Bluff. It emerged during a period when engineers were experimenting with new reinforced concrete techniques for river crossings.

The National Register of Historic Places listed this bridge in 1981, marking its importance in California's transportation development and engineering advancement.

The bridge sits in a rural area west of Bridgeville requiring travel through secondary roads in Humboldt County. Visitors should check road conditions before driving and allow time to locate it off the main highway routes.

The structure appeared in the 1995 film Outbreak when a helicopter flew directly beneath it during a chase scene over the Van Duzen River. This film moment added an unexpected connection to cinema history for a quiet engineering landmark.

Location: California

Architects: John B. Leonard

GPS coordinates: 40.48056,-123.88944

Latest update: December 14, 2025 18:13