Deeping Coomb

In J. R. R. Tolkien's fictional universe of Middle-earth Deeping Coomb is the deep, well-defended valley in the northern White Mountains that held Helm's Deep and the castle of the Hornburg. The site of an important battle, the Battle of the Hornburg, during the War of the Ring.

The word coomb is a rare Celtic Brythonic survival word; meaning a small deep dry valley, easily defended. It gives its name to many places in the British Isles.