Menegroth (the 'Thousand Caves') was the greatest Elven city in the First Age of Middle-earth, being unrivalled in beauty and complexity throughout history. It was created for Elu Thingol in Doriath by the Naugrim dwarves. While the main part of the city was delved deep into the earth, there were further buildings on the surface of the earth.

The city started with the Gates of the Hall of Thingol on a rocky hill with the River Esgalduin at its feet. There was a bridge of stone over the river – the only way to access the Gates. From there, wide passages ran down to high halls and chambers hewn into the rock. The Hall of Thingol was a great pillared room with a roof of stone and it contained thrones for Thingol and Melian. Also included in the city were armouries and chambers for the Dwarves of Nogrod and Belegost when they needed accommodation.

While the city was excavated by the dwarves, the influence of Melian the Maia was shown through the woven hangings showing Valinor, the deeds of the Valar, many things that had befallen in Arda, and shadows of things that were yet to be. The pillars of Menegroth were shaped like beeches, and were lit with lanterns of gold. Nightingales sang there and there were fountains of gold, basins of marble and floor of many-coloured stone. Figures of beasts and birds were carved everywhere.

The lands near the hill were also used. Lúthien’s house, for example, was in the branches of Hirilorn.

The city was never truly finished as it was destroyed in the feud between Thingol and the Nogrod dwarves. Dior later attempted to restore Menegroth, but then the sons of Fëanor took the city, and the restoration failed.