Gates of Toth..........how do you open the door?

To get to the other side of the gate of Toth you have to first complete the mission to get rid of the darkspawn.  When you close the tunnel you can exit the dungeon on the opposite side from which you enetered and make a camp.  The access to the gate of toth is in the area that is now open to explore through that camp.

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@lesommeil2329 wrote:
Go into Coracavus, take the south exit into the echo back canyon camp, and then it will take you along a back route. It's literally a gate and that's it. An utter waste of time that took me the better part of 30 min to find... Now if only I could get the discover samson's weakness mission back on my dang war table

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OK, I'll try it again...btw on the Samson thing, IIRC you have to talk to Cullen several times and also the dwarven enchanter chick is somehow involved...but it's a bit fuzzy in my memory, I may be conflating it with the eavesdropping crystal thing. I do know that by the time I was in a position to get the mission, I had already crushed Samson and his lousy red templars into dust...

I had to deal with this one today. Hopefully, I'm giving the correct answer. Once you've cleared Echoback, which is to the north, you go south and curve around the desert, until you find the (for me) final landmark and a switch that opens the gates of Toth. 

you have to do the "Trouble with Darkspawn Mission"

you leave the keep. and travel roughly west, northwest....

you'll get to a pile of lumber, and maybe a partialy built wooden bridge.

claim it to open another mission in the war room, to get past the poison gas storm,

with that you'll be able to get past the gates of toth. and open them from the other side.

Hiii im portuguese so sorry for comon mistakes on that map on the north...theres is a place called CORACAVUS go there complete it, in the end you are where you wanna go i think

Thank you...finally figured it out! :-)

Part of my problem is that both sides of the Gates of Toth look substantially identical, except for the (well-hidden) lever that allows you to open them...so I probably "found" them several times without realizing it! :-)

You go through the prison that you have to enter to finish the quest The Problem With Darkspawn, across the bridge built by war table operation close to Griffon Wing Keep. Once you go although through the prison, past where you fight  the giant, there is a place where you set up a camp, etc, and take down Servis in Echoback Fort. From that area you can reach the other sides of the Gates of Toth, where there is a lever you pull to open them permanently.