Fortress Explorations is technically a part of Tokyo Disney Sea's Mediterranean Harbor, but it occupies the part of the park that is geographically Mysterious Island. Call it a territorial acquisition, I suppose. With the looming volcano of Mount Prometheus beyond, it does look like a fiery mountain background in an Italian countryside. Plus, Mysterious Island doesn't really reveal its retro-futuristic steampunk architectural aesthetic until guests venture into the caldera, so the set functions double duty as both backdrop and enveloping world boundary. That gives Fortress Explorations--really just an oversized playground area--a fantastic setting. Here are a few angles of this wondrous area to showcase exactly how this all conveys!