I've walked across (twice) a bridge I'm willing to bet that few, if any, people here (other than older, native Pittsburghers) have crossed on foot: the former "bridge to nowhere" Fort Duquesne Bridge (I-279) over the Allegheny River, at the Point of the golden triangle of downtown Pittsburgh. The reason I being that few have done this is that it is NOT a bridge that is normally open to pedestrian traffic (nor does it have scheduled "bridge walks"). But back in the summer of 1970 during the first season of then-new Three Rivers Stadium, my cousins & I went to a Pirates game. Due to delays in construction, the parking lots at the stadium were still unfinished, requiring most event attendees to park downtown and walk across the river to the stadium. The official pedestrian route was to use one of the "Three Sisters" bridges (now known as the Roberto Clemente, Andy Warhol, & Rachel Carson bridges), but this meant walking a few blocks out of the way. The Fort Duquesne bridge was officially off-limits to those on foot, since it carried an interstate highway (which then immediately ended there in the North Side borough). But the structure did have a maintenance walkway, which required a several-story climb & descent on either riverbank to access. By mid-August, local cops had given up on keeping people off of that very convenient shortcut. So we parked at the Gateway Center and walked the Bridge to Nowhere to get to the Pirates-Dodgers game!
Other significant bridges I have walked are:
∙ the iconic Golden Gate Bridge (US 101), on October 17, 1989, the day of the Loma Prieta earthquake, no less. Fortunately, I did it several hours before the temblor!
∙ the Mike O'Callaghan - Pat Tillman Memorial Bridge (US 93, soon to also be I-11) over the Black Canyon of the Colorado River between NV & AZ just downstream of Hoover Dam.
Note: After posting this I discovered that the Ft. Duquesne Bridge walkway IS actually open to the public these days. Not sure when that became official, but back in 1970 it wasn't supposed to be. Does anyone know if it's twin, the Ft. Pitt Bridge, has a similar walkway and if so, is it also open to the general public?