Guild Wars 2

Hello,
Was wonder what this area was for?
Was it a scraped idea, an event, or what used to be involved?

Thats were the last story missions take place.

That is, quite literally, The Heart of Thorns. Its where the last two chapters Dark Harvest and Heart and Mind take place. By the time you arrive (you = PC), the pact and alliance of guilds is on your tail. You kill the mordrem faolain, and enter the heart of thorns.
This is where is gets interesting. When you enter the Heart, the war in the open world begins. This is a very interesting design, because of the fact that you’re attacking the mind of mordremoth and the pact+alliance attacking the heart, is whats making this war possible. Mordremoth cannot focus on both sites, so in the chaos its a war fought on two fronts. I really recommend you complete the story and simoultaneously do both last missions for the best experience.