Corin Entrance
Corin was built by an ancient Order called the Sentinels of the Mercifull Sword , it was built as a prison for a long dead demon whom was Banished by Tyr and Torm during a Demonic invasion in the Upper Planes, the banished soul of the demon and his minions were entombed in Corin and put under the protection of Torm, Helm and Tyr's followers so that they may never return to their infernal home. Corin became a site for pilgrims wishing to pay homage to the gods and their victory over the demons, it became a holy site revered by many of different religions and cultures.
Following the cataclysm and the ensuing spellplague the layline that had been the source of Corins magical defences violently erupted, opening a tear to the underdark, sending most of Corin into ruins in the darkness below, it is believed that his rapture had killed the captive demons, allowing them to finally return to their infernal plane once more. The rapture sent most of the landmass around Corin aloft into floating earth motes, these earth motes circle the ruined Layline where Corin once was and is now home to the Arakroa and Goliath city of Heavensward .
Now Corin is only a husk of it's former self, only the entrance and the temple remain, the rest has sunk into the depths. Fragments of Corin still remain intact, many adventurers and explorers alike has ventured it's depths but none have fully probed it's sprawling maze as the deepest layers are home to aberrations and fiends that still reside there. It is said that the gods themselves have abandoned Corin and that the ruins are destined to never be restored, yet the Sentinels of the Mercifull Sword still remain in Corin, intent on its protection and restoration.