1) Giant. If people have real reason to be there AND you can make them stay there (bearcharge?) then maybe you can land a kill.
2) Underdark. Good luck just blind camping it though. It may be hours until someone comes through. Even then, they have to be dumb enough and stay and not run for the exits as soon as they realize you're (cavern?!) ranger. Like the log above, where they stayed by choice with no prots while getting outdamaged.
3) Maethien ruins, but only if you manage to sneak in unnoticed AND they're in the wild parts still with no repop behind.

Honestly, your general str evil ranger camping Fort is getting 10x the action in the meantime.

Not to mention ANY Scarab/Reaver, who can arguably fight anyone else anywhere.