You can get around outside the play area by using Flash Attack if there are enemies there (in one section of the mountains in the Dark Forest and sometimes in the sewers), but if you can not teleport out, you will need to leave an enemy alive to get back out (you can not walk in most places outside the normal play area).
You can also toss a teleporter stone into various places to teleport there (as in
a way out, if you're Stuck in the Easter Egg Area), or more technical,
Teleporting Anywhere, via hex editor.
To clear as much fog-of-war as possible, try a combination of;
- Max Elven Sight (much more effective) and Ranger Sight (if you have the skill points to spare and really want to maximize your sight range).
- Keep any equipment you find with sight bonuses, to use when exploring.
- Toss a teleporter stone onto/into inaccessible regions and move around by repeatedly tossing one stone and teleporting to it (you are not suppose to be up on most mountains, across the river in the south east corner of the dark forest, etc, and will not be able to walk there).
- Cast Wizard's Sight twice in the same location (cast it a second time before the fog-of-war fills in again from the first, and it will remain clear). Hold the shift key down to move the screen focus away from your character and towards the area you want to clear.
The results of other people's explorations can be found in the topic;
EASTEREGGS and RUNE manuscripts 
