Helms Deep is a large valley in the north-western Ered Nimrais (White Mountains). The valley is blocked over its entire width by the natural series of hills called Helm's Dike and behind that lay the fortress of Aglarond or the Hornburg, at the entrance to the Glittering Caves.
In the Two Towers the fortress at Helm's Deep becomes the refuge of the main army of the Rohirrim, under King Théoden during the War of the Ring. Théoden said that "the Hornburg has never fallen to assault" giving an impression of invulnerability. This was tested during the Battle of the Hornburg, as a massive army of Uruk-hai sent by Saruman almost overwhelmed the defences of the Rohirrim. Saruman's orcs used an explosive blast of fire within the culvert which, when detonated, breached the long Deeping Wall. The origin of this explosion is unclear and Tolkien denotes it as "Saruman's devilry". The Rohirrim defenders held out long enough in the fortress until dawn, giving Gandalf time to gather and lead a counter-attack, while Théoden led a cavalry charge that drove the Orcs from the fortress.
Please note that due to the terrain the co-ordinates may not be accurate. We have done our utmost to ensure that they are as good as possible. Please take spoiler photos with you, you will not have mobile signal at gz.
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