Great Tomb of Nazarick

The Great Tomb of Nazarick (ナザリック 地下大墳墓, Nazarikku chika dai haka) is the headquaters of the 41 Supreme Knights. This dungeon in the Kingdom of Ishval was seen to be unconquerable, but was conquered by only 41 Spell-Casters, while whole armies of over 500,000 count not.

Background
Before the 41 Supreme Knights took over. The Tomb was between to kingdoms in conflict of conquering it. However, the kingdoms, and the monsters of the Tomb fought for over 300 years. Soon, the two kingdoms of Ishval and Valion teamed up to conquer it, but still failed when the most of their soldiers were wiped out on floor 3-6, forcing them to retreat.

After another 10+ years, the guild of Arial Rise, now called the 41 Supreme Knights went, and conquered the Tomb.

Trivia/Notes

 * Heavily based after the Great Tomb of Nazarick in the Overlord Series.