The value you are looking for is the location_type.
Code:
SELECT s.value, w.location_type FROM WorldLocation w LEFT JOIN StringResource s ON w.text_id = s.code
Trainee Island has location_type 3, towns usually 1.
BattleField = 5,
Dungeon = 4,
Etc = 0,
EventMap = 7,
Field = 2,
FleaMarket = 10,
HuntaholicDungeon = 9,
HuntaholicLobby = 8,
NonPkField = 3,
Town = 1
(Source: Rappelz Emu)