[nwallin]

These are light rail/tram tracks, not railroad tracks. The road is the same type of road that you normally drive up, they just have train tracks embedded in the road surface, signs telling you not to drive there, and every now and then a tram drives along it.

Functionally, they're no different than bus lanes or a wide shoulder. Humans drive on them all the time, because there's no traffic on them and they can get to where they're going faster. They shouldn't, it's illegal, and they can get ticketed for it, but they do it anyway. If you load up google street view in Phoenix/Tempe/Gilbert you can see a few people driving on them.

[lokar]

People have been getting confused and driving cars towards/into the SF muni tunnel for ages.

[drob518]

Okay, so this is tracks embedded in and parallel with road surface, not tracks with cross-ties, sitting on ballast. That’s a bit more understandable, then.