Well, yeah, hard (as of March 20th). Regarding source, as you can see in this changeset, `source=survey` and imagery_used=.gpx data file` (my own track when I went there). I've also mapped barriers with geolocated photos.

Most of the path I've tagged with `trail_visibility=bad` and one part is even `sac_scale=alpine_hiking` as you have to even climb almost vertical wall - the path are there though (mostly). And yeah, plenty of `barrier=log` throughout.