Calacirya

Calacirya (meaning "White Ship" in Quenya) is the pass in the Pelori north of Taniquetil where Tirion was set on Túna. After the hiding of Valinor this was the lone gap through the mountains of Aman. The Valar would have closed the mountains entirely but, realizing that the Elves, even the Vanyar, needed to be able to breath the outside air, they kept Calacirya open. They also did not want to wholly separate the Vanyar and Ñoldor from the Teleri on the coast.