|Inhabitants||Rohirrim refugees, later Dwarves|
|Events||Battle of Helm's Deep|
|References||The Two Towers, The Return of the King|
The Glittering Caves were located behind Helm's Deep under the three peaks of the Thrihyrne in the northwestern arm of the White Mountains. Gimli called the Glittering Caves one of the marvels of the Northern World. The Glittering Caves extended deep under the mountains, with many passages, stairs, halls, and chambers. The floors were sandy and the ceilings were high, domed vaults. The walls were polished stone set with gems and crystals and veins of ore.
War of the Ring
During the Battle of Helm's Deep on March 3-4, 3019, many of the women, children, and elderly people of the Westfold took refuge in the Glittering Caves. Livestock and food were stored there as well. The entrance to the caves was behind the Deeping-wall in a narrow gorge that could be defended long against an onslaught.
Some Orcs crept through a culvert in the Deeping-wall and entered the gorge but were killed or driven back by the defenders. Then the Deeping-wall was breached by an explosive device and the Enemy forces entered the Deep. Many of the Rohirrim including Eomer were driven back to the Glittering Caves, and with them was Gimli.
As a Dwarven Colony
When Gimli Elf-friend was held up in the caves, he was amazed by their beauty. After the War of the Ring he brought from Erebor part of Durin's folk and founded a colony in the caves, becoming the first Lord of the Glittering Caves. The Dwarves of the Glittering Caves carefully tended the stone walls and opened new ways and chambers and hung lamps that filled the caverns with light. The Glittering Caves became one of the most important realms of the Dwarves at the beginning of the Fourth Age.
The Glittering Caves are one of very few locations in Tolkien's work that are associated with a real place. They were inspired by the Cheddar Gorge and Caves in the southern English county of Somerset.