Annakarl

Annakarl was one of Zaros' fortresses that was located in what is now the Wilderness. It was captured by the early Third Age and destroyed during the Third Age by followers of Zamorak and Saradomin. The Demonic Ruins in level 47 wilderness are all that remains of Annakarl today, and you can teleport there with the Annakarl Teleport spell.