 In Sub-Level 6 of the Batcave, there's an aqua-dynamic hydrofoil/submersible (otherwise known as the "Batboat") on both the navigable Gotham River and the Atlantic Ocean's waters.Early in his career, while investigating arms dealers operating along the wharves of Gotham City's Chinatown district, Batman used a prototype Batboat to pursue the fleeing criminals.In what was later regarded as an "extreme measure", Batman destroyed their launch with a bow-mounted flame-thrower.