Tumladen was a green field located in the middle of the Encircling Mountains where the great city of Gondolin was founded and located. In the middle of Tumladen was a small hill made of smooth stone, called afterwards the Amon Gwareth. This stone hill was the foundation for the city Gondolin built by Turgon. Tumladen and the city it contained remained secret and safe for 503 years since the Return of the Ñoldor to Middle-earth. It was, however, betrayed by the father of Túrin Turambar, Húrin Thalion, when Húrin shouted at the mountains encircling the city to let Turgon know to open the gates and let him in (this was an ill-fated attempt, for no one heard him, and Húrin despaired). As Húrin was under the spell of Morgoth, the Dark Lord finally learned of Gondolin's location through Húrin. I