Where to find the purple secret key in Siege Part 1 in Doom: The Dark Ages

In Doom: The Dark Ages' sixth mission, Siege Part 1, you'll run into multiple secrets that require the purple key. Most of the time, the keys and keycards you need are close to the secret you're trying to unlock, but that's not the case here.

Since the map is massive and multiple Doom: The Dark Ages Siege Part 1 secrets require the purple key, it can be quite a trek, especially if you don't know where to look. To save yourself some trouble and get back into the action quicker, here's where you'll find the Siege Part 1 secret key.