The Boone Bridge is a bridge located in Clackamas County, Oregon, right next to Wilsonville that crosses the Willamette River and carries Interstate 5. It was completed in 1954, replacing Boone's Ferry (which was opened in 1847, by Jesse Boone, the grandson of Daniel Boone), and completing Interstate 5 in Oregon. It is a few thousand feet long (the Willamette is about 700 feet wide at this point), and six lanes wide.
In my writeup about the Yaquina Bay Bridge, I said that that bridge was the most beautiful and most indispensable bridge in Oregon. But I have to admit that the Boone Bridge, which connects the Portland area with the Willamette Valley and all points south, and which carries people and cargo into the Portland area, is perhaps more indispensable, since if it closed, the alternative would be to route traffic a dozen miles in either direction along small roads. But the Boone Bridge won't win any prizes for beauty or architectural innovation. It is a concrete deck along concrete supports. It isn't a bridge as much as it is a road over water. I am sure that there was engineering challenges involved in making a bridge over the Willamette, but I've ridden over this bridge probably hundreds of times in my life, and it didn't evoke much emotion, or even really the acknowledgement that I was on a bridge. Even Bridgehunter, which tirelessly chronicles every bridge, no matter how small and unimportant, strangely doesn't have an entry on this bridge. The Boone Bridge is a good example of how modern infrastructure can be so functional that people don't even realize it exists.
That might change soon. Like many bridges built before we knew what plate tectonics were, the Boone Bridge is going to be either retrofitted or rebuilt in the coming decade to deal with the threat of a Cascadia Subduction Earthquake, and perhaps its replacement will be somewhat more architecturally interesting.