Amon Gwareth.

The Hill of Watch.

The hill of hard smooth stone in the hidden vale Tumladen where Turgon builded the city Gondolin. The stone was carved by water because the vale had in ancient days been a lake. On the North side of the stone-hill was Caragdûr. Amon Gwareth was 400 feet high and appear as having a flat circular summit 3000 feet North / South and East / West. The sides of Amon Gwareth was impossible to climb as springs wet the glassy and steep rock and the sound of the water running down inspired Gondolin`s original name Ondolindë, The Rock of the Music of Water.