§ Of Tuor and the Fall of Gondolin The Silmarillion

And at the last by the power that Ulmo set upon them they came to the hidden door of Gondolin, and passing down the tunnel they reached the inner gate, and were taken by the guard as prisoners. Then they were led up the mighty ravine of Orfalch Echor, barred by seven gates, and brought before Ecthelion of the Fountain, the warden of the great gate at the end of the climbing road; and there Tuor cast aside his cloak, and from the arms that he bore from Vinyamar it was seen that he was in truth one sent by Ulmo. Then Tuor looked down upon the fair vale of Tumladen, set as a green jewel amid the encircling hills; and he saw far off upon the rocky height of Amon Gwareth Gondolin the great, city of seven names, whose fame and glory is mightiest in song of all dwellings of the Elves in the Hither Lands. At the bidding of Ecthelion trumpets were blown on the towers of the great gate, and they echoed in the hills; and far off but clear there came a sound of answering trumpets blown upon the white walls of the city, flushed with the rose of dawn upon the plain.