#tollkien
TheCrissaegrim were a mountain range, forming a part of the southern Echoriath, the Encircling MountainsofGondolin, and were inaccessible from the ground. However they were home to the great Eagles, and from here Thorondor, Lord of the Eagles, watched for spies in the vale of the River Sirion. Indeed, the Eagles were the chief source of information to Turgon and the Gondolindrim.
Crissaegrim is a Sindarin name that includes the root kris-. meaning “Cleft Mountain Peaks”. It is usually referred to as the “Abode of Eagles”.
It was from the Crissaegrim that Thorondor espied HúrinandHuor when they were lost in Dimbar. The Lord of the Eagles sent two great birds to carry the men above the Crissaegrim into Tumladen, when King Turgon of Gondolin welcomed them.