You can get to the metzone through the MarketController or whatever the Npc's name is that allows you to leave, theres an option to go to the met zone.
It brings you to the start of the walk towards the metzone, continue to the top left of all maps untill you reach a map with a river in the center, jump the river where the two sides are closest then continue to the top left there will be a man standing there talk to him and bam ur in the met zone.
Enjoy