Guild Wars 2

Where was the The Great Temple of Balthazar located in GW1? Was it in the sea of sorrows or further south?

It was on a chain of islands located between Tyria and Cantha. Relatively near the center of the Unending Ocean.

those islands submerged when Orr rose, though one would assume they’d be on the map again by now.

Unless they are fully submerged like Lion’s Arch.