The Plaque has historical information
The FTF will see some big Money (Play) in this cache, along with an unactivated Trackable
This cache is on Private property and not on the Bridge, the property owner is aware of the cache. It can be reached from the parking Area.
Fernbridge is a 1,320-foot-long (402.3 m) concrete arch bridge designed by American engineer John B. Leonard which opened in 1911 at the site of an earlier ferry crossing of the Eel River. Fernbridge is the last crossing before the Eel arrives at the Pacific Ocean, and anchors one end of California State Route 211 leading to Ferndale, California. When built, it was named the "Queen of Bridges" and is still the longest, functional poured concrete bridge in operation in the world.
More Bridge History is at: This is a link