It was here that Thorondor, Lord of the Eagles lived, and from here he watched for spies in the vale of the River Sirion. Indeed, the Eagles were the chief source of information to Turgon and the Gondolindrim.
Other versions of the legendarium
In early versions of the Quenta Silmarillion, Tolkien used the name Gochressiel, which he amended to Crisaegrim (later spelt Crissaegrim). Christopher Tolkien has noted that the former name might not have referred to this southern section, but rather to the whole of Echoriath.