do they go both directions on one side of the rail though? at least in san francisco when i was there they didn't.
They might not go both directions on the same line, but they must loop around in some manner, or else all trams would just go to a dead-end.
So you could be heading the direction that the trams go, but then have one come up from behind you.
You're not likely to have a head on collision with a tram unless you're particularly stupid and go the wrong way.