That's San Jose Avenue, not Alemany, in the Bernal Cut while it was under construction. The track was the original SP main line into SF before the Bayshore line was built. If my olde books are correct, the cut also carried Ocean Shore RR tracks (gone by 1930). Not sure which, but there might have been a Muni streetcar line there too, before the tracks went away some time in the 1940s-early 50s and it was converted to all road. In the 1970s, the bridges were rebuilt without columns in the center so the road could be improved, then more recently the J light rail line was extended through there returning rail service to the area.

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