Single-photon light detection and ranging (LiDAR) has broad applications ranging from remote sensing to target recognition. In most cases, however, the repetition period of the pulsed laser limits the maximum distance that can be unambiguously determined. The relative distances are normally obtained using a depth map. Here, we propose and demonstrate a photon-efficient three-dimensional (3D) imaging framework which permits the operation of high laser pulse repetition rates for long-range depth imaging without range ambiguity. Our approach uses only one laser period per pixel and borrows the information from neighboring pixels to reconstruct the absolute depth map of the scene. We demonstrate the absolute depth map recovery at ranges between 2.2 km and 13.8 km using ∼1.41 signal photons per pixel. We also show the capability to image the absolute distances of moving targets in real time.