TirionTirion - When the Noldor arrived in Aman, they tried to live in Valinor, the land of the Valar.  But the light of the Two Trees shown brightly and the stars could not be seen.  The Noldor longed to look upon the stars as it reminded them of their first home.

 

"...and therefore a gap was made in the great walls of the Pelóri, and there in the deep valley that ran down to the sea the Eldar raised a high green hill: Túna it was called...Upon the crown of Túna the city of the Elves was built, the white walls and terraces of Tirion; and the highest of the towers of that city was the Tower of Ingwë..." ~The Silmarillion, chap. 5 (Of Eldamar)