Argonag

Argonag was a massive fortress built by Limryn and his forces upon his expellment from Loriendil's realm. It lay in the mountains of Northeastern Haven, and was the eventual site for the Imperial City upon the Argonag's dismantlement at the end of the First Age. During the War of Ages, Limryn used the Argonag as a home base for his entire operation, and he spent most of his time within it's walls. Created using dark magics from the Fade, Argonag drew other creatures and demons from the Void to it. So much magic was used in its creation however, that Limryn nearly tore the barriers between the mortal plane and the Void asunder in the process, and to this day the Imperial City is a place where mages are more connected to the other realms, and are therefore more apt magically.