I loved levelling in Arathi highlands and Southshore. Back there, allies and hordes always clashed around there, making the zone very interesting to be in especially in PVP realms.

An innocent ally will call for help being continuously ganked, then a 60 will help and camp, and soon you get guild wars there leading to raids in refuge point.

Its also a place where people que for Arathi Basin and quartermasters were there, so many big shots Grand Marshals and the marshal teams will show the hordes what it's like messing about lol..

All zones are great in WOW, prob the least fav one to me is Blasted lands (before portal to outlands)