Original written by Aribeth the Ranger:-

Speak to Minister Of Maintenance Raiugyon in Kaineng Center

Enter Bukdek Byway from Kaineng Center and follow the quest marker. You will reach the Chasm - just click it to enter and proceed to the Tunnels Below Cantha. Now fight your way through the groups of Am Fah, the entire area will have a graphical effect similar to Cathedral Collapse, but without any side effects. Because Am Fah Assassins can block very well, you should consider bringing spell casters instead of melee characters. Follow the way where enemies are and you will reach some dwarvens. Vekk and Ogden Stonehealer will also be there. A cutscene will start after which you will automatically get the quest The Beginning of the End. You will get the reward once you go through the Asuran Gate.