Writer Mark Haskell Smith used clues provided by Anthony Kiedis in interviews and his memoir, Scar Tissue, to determine the bridge in question. In 1992 Kiedis told Rolling Stone that the bridge was in downtown Los Angeles, but he insisted that "it's unimportant. I don't want people looking for it." In his book, Kiedis wrote about the rock-bottom period that inspired the song, and noted that he would often walk to Sixth and Union Street in downtown L.A. from his friend Kim Jones' house.
Smith ruled out several bridges in this area before determining that it is most likely that the singer was referring to a small pedestrian tunnel underneath Wilshire Boulevard cutting through MacArthur Park, which was a major drug spot in the late Eighties. Smith shared a photo of the bridge as it is today in broad daylight. It doesn't look particularly seedy, but it's not too hard to picture it in a more grim period of the park's history.