The Saint-Denis Temple was an Isu temple located beneath the commune of Saint-Denis in France. Until 1794, the temple housed the Head of Saint Denis, a lantern fueled by the power of an Apple of Eden. The temple could not be accessed without the relevant key; any attempt to pick the door open would cause it to emit a lethal energy blast.
At some point in the first half of the 12th century, the temple was found by the abbot Suger of Saint-Denis. Using the knowledge gained from the Apple of Eden housed within the lantern, Suger created the Eagle of Suger, a powerful sword adorned with a golden hilt.
In August 1794, Napoleon Bonaparte directed a contingent of French soldiers and raiders, led by Philippe Rose, to Saint-Denis to find the temple, after having previously acquired the key to the temple's main doors. Despite the efforts of the former Assassin Arno Dorian, the raiders managed to enter the temple, though they were ultimately routed by Arno using the power of the Head of Saint Denis. After making his escape from the temple, Arno sent the Apple of Eden to Al Mualim in Cairo and kept the Head as a memento.
- A symbol resembling the Assassin Insignia can be seen in the pillars of the temple, where the main door is located.
<gallery captionalign="center" position="center" spacing="small" widths="180"> ACU DK Saint-Denis Temple Exterior 01 - Concept Art.jpg|Temple exterior ACU DK Saint-Denis Temple Interior - Concept Art.jpg|Temple's inner chamber ACU DK Saint-Denis Temple Exterior 02 - Concept Art.jpg|Temple exterior ACU DK Saint Denis Temple - Concept Art.jpg|Temple overview ACU DK Saint Denis Temple Door 02 - Concept Art.jpg|Temple entrance ACU DK Saint Denis Temple Door 01 - Concept Art.jpg|Temple entrance