> "They went out onto the ship then, and An pondered where to put
> himself, so as to cause the maximum inconvenience to everyone."

Very good! (Assuming I understand it myself :)

Eysteinn Björnsson pointed out to me that there are
other instances of "hvar + gen." meaning "where in X".

hvar lands = where in the land
hvar skips = where in the ship

This locative use is mentioned here: