Submarine amusement ride

An underwater mobile observatory system comprising an aquarium above to hold water and large enough to support fish, coral, and to display artificial objects a vehicle track extending through the aquarium the track generally being adjacent the bottom of the aquarium, the track having a portion which rises to a loading/unloading position, at least one passenger vehicle slidingly locked to the track for movement therealong and unable to be lifted from the track such that inclination of the track causes the vehicle to move up and down through water in the aquarium, the passenger vehicle having main body portion to seat passengers and which is capable of being submerged, and a top portion which is open to the air, the spacing between the track and the water level being controlled such that water does not pass over the top portion, and a walkway provided above and substantially along the track above the waterline to allow the at least one passenger vehicle to pass below the walkway with the walkway being accessible via at least one exit hatch in the top portion of the vehicle.