At TC, goes to your left side where the Training ground entry.
A lady (Guild conductress) stand beside the old man.
Talk to the guild conductress, she let you in.
There are 4 conductress in the guild area.
Normally guild conductress 1 is going to Advance Zone but subject to the guild who won the last Guild war.
Advance zone is mainly magic attack. Level 40 is normally hard to survive there.
If you get killed and you revive, you will be send to stone city.
I suggest you view the map at the conqueronline website to understand better (^^)
DM