Underwater express, a train which runs under the water. It starts from the Mumbai underwater terminal(A city in Maharashtra, India) and ends at the Underwater amusement park(An 1024 square ft amusement park under the pacific ocean and near Japan)covering the distance of 44,000 KM at the speed of 1040 KMPH(sounds like hyperloop yeah?).
TRIVIA: The underwater amusement park is also known as Underwater dream land & underwater fun land.