Calacirian

Calacirian was a region of Eldamar near the entrance to the ravine of Calacirya. The hill of Túna stood there, with the city of Tirion built upon it. The light of the Two Trees was the strongest there in all Eldamar.

The name appears in Bilbo's Eärendillinwë in Rivendell:

and seven lights before him sent,
as through the Calacirian
to hidden land forlorn he went.