A towed vessel suitable for containing and transporting various liquids is disclosed. The vessel further comprises various features useful in the transportation, navigation, and storage of the towable vessel, both when in use for transporting fluids and when transported in an emptied state. Such features include navigational and positioning devices and methods, power supply devices and methods, and means for filling, inflating, emptying, and deflating a non-rigid, towed vessel. Aspects of embodiments of the present invention further include features useful for purifying or preserving the purity of the fluid to be transported.