There's no easy way to see it at the moment, other than looking at the waypoint list (the box at the top left). One idea I'm looking at is putting arrows on the line - so in this case you'd see arrows going both ways on the line.

And yes, the numbers do not represent km, they represent the numbered waypoints listed in the top left box. Any usability suggestions are very much welcome!

Thanks, yes. I think it would be nice to have some kind of range indication, maybe the waypoints could be letters so they don't get confusing?

And then you can toggle distance measurements.

And for the direction problem, maybe a change of color every kilometer or a gradient? Although that might also be confusing.