A couple years ago I read about a hiker who left a footpath and stepped on a World War 2 land mine. While most of the footpaths are well defined by a path of rocks - there were a couple times when the footpath I was hiking disappeared - very nerve wracking to say the least. Stick to well defined paths.
Thinking of renting a scooter? Think twice and go slow. First off, only one place rents them in Vis and they are tired scooters. The brakes suck and the tires are well worn.
So, still want to get around the island on your own schedule and hit the beach or wander some tiny village, okay but remember to take it slow, the road into Komiza from the south has long drops and no railings. From Hvar to Korcula and back to Vis you either hear or will see for yourself those that have suffered the indignity of the scooter crash. Fortunately it seems that most of these crashes are single vehicle accidents that range from some nice road rash to broken wrist and arms. At least it only cost the one American we met $40 US to have his nasty broken arm set back in Split.
WEAR A HELMET!