can't access the area South of Boreas Seabed

I have several quests that lead to the area south of Boreas Seabed, but I can't seem the access this area. I've tried getting to it from every nearby outpost. The eastern gate in Boreas Seabed is closed to me. The green star on my map tells me to go through this gate.

Thanks so much for your help!

Try going through Pongmei Valley > Mount Qinkai and round the side.

To exit east from Boreas Seabed into Cavalon you'll need (if I remember correctly) to get the quest 'Befriending the Luxons' and then 'Journey to Cavalon'. If you have been doing things Kurzick side then you may not have unlocked Cavalon yet in this way.

A character of mine that was working on the Kurzick track but wanted some Luxon armour pieces was able to go round from Pongmei > Quinkai then east from there through an outpost (can't remember name) then Archipelagos and into the Southern entrance of Cavalon. Note that there is no way to the the equivalent and sneak round the back of House zu Heltzer. It's strictly linear there.

I might be wrong, but isn't that the area you visit in the first challenge mission in Luxon area?

What's it's name?