just to clear this up, heres how to get to tyria from cantha:
Factions characters wishing to travel to Tyria for the first time should seek out Guardsman Chienpo in Kaineng Center and take the "Chaos in Kryta" quest.
Prophecies characters may travel to Cantha using the quest "Mhenlo's Request," which is offered by Firstwatch Sergio in Lion's Arch.
(copied from http://www.guildwars.com/support/gameupdates/ updates for thursday, april 17)
