RPG Insanity

Where is Enten Hall and how do I get there? The guide says it's west of Donga, but west of Donga I only find certain ruins I can't access yet and then the lands end and I can't cross the sea (see image).

Do I have to go north though the mountains or something?

You have to go back to Donga and go all the way west of the city to an exit that takes you to Enten hall. Its actually in Donga.