A circulated pneumatic tube transit system is used to transport passengers/cargo along a pair of pneumatic tubes, which are positioned along each other. Capsules are movably suspended within the tubes by either a maglev system or wheels. The capsules travel in opposite directions in each tube so that the system provides back and forth transportation between two destinations. A fluid loop mechanism cycles a volume of air through the tubes as a means to propel the capsules through each tube. A series of fluid loop mechanism can be air multipliers as the volume of air cycles through the tubes. Two one-directional valves are located at opposite ends of the tubes and are used to transfer the kinetic energy for an arriving capsule within one tube into kinetic energy for a departing capsule within the other tube.