The Entrance
The Firehouse is an Gigantic bunker under the city where Fireblaze makes his home, it is mainly a lab filled with the newest technology available.
This includes perfected cloning to machines capable of creating pocket dimensions, Fireblaze oversee's everything that happens in here. With this powerful technology held inside it is obviously top secret and nearly impossible to break into the only two ways being a massive assualt when Fireblaze himself opens the door, or utter destruction on the city to blow it open with extremely powerful explosives.
Nobody but Fireblaze can open the door UNLESS Fireblaze is inside and enters a passcode that only a Phoenix (The race of which Fireblaze belongs to) could enter.