We took this shortcut on 939/Alternate-1 over the highlands as we were running late. Other smaller 2WD vehicles seemed to make it without trouble although the road was on the worse end of what we encountered in Iceland. It got rather steep at the end (with a grade of 17%!). The speed limit of 40 kph is highly optimistic for the conditions. We later learned it was prone to rockslides, but we did not see any recent ones. On the plus side it had a great view of Berufjordur coming down, and two very picturesque but un-named waterfalls.