Sharn Wall

The Sharn Wall, also seen as Sharnwall, was a shimmering, silver-colored magical barrier in Anauroch created by the sharn to imprison the phaerimm, an ancient, malevolent, and powerful race that were imprisoned beneath Anauroch by the Sharn after the collapse of Netheril.

History
In 329 DR, the sharns finally defeated the phaerimms, thus halting the spread of Anauroch. They imprisoned them behind the Sharn Wall beneath Anauroch, in the Buried Realms, which the phaerimms called the Phaerlin.

In 464 DR, the vampire Palron Kaeth sought to destroy the Sharn Wall and release the phaerimms using the blood of Khelben Arunsun and his father, but the two mages sacrificed themselves to stop him by using the Lupinaxe to shatter the Duskstaff of Sarael, causing a massive explosion in the sands of the Sword.

In 1371 DR, the Sharn Wall was punctured by an explosion caused when magical bolts produced by Galaeron Nihmedu, a Weave caster, and Melegaunt Tanthul, a Shadow Weave caster, collided. Magic from the Weave and magic from the Shadow Weave mingled with disastrous effects. This freed the phaerimms from their prison, allowing them to strike out into greater Faerûn.