We have recently demonstrated smooth and controllable matter-wave guides by transporting Bose-Einstein condensates (BECs) over macroscopic distances without any heating or decohering their internal quantum states [9]. A neutral-atom accelerator ring was utilized to bring BECs to very high speeds (up to 16 times their sound velocity) and transport them in a magnetic matter-wave guide for 15 centimetres whilst fully preserving their internal coherence. We then use a magnetogravitational matter-wave lens to collimate and focus matterwaves in ring-shaped time-averaged adiabatic potentials. This “Delta-kick cooling” sequence of Bose-Einstein condensates reduces their expansion energies by a factor of 46 down to 800 pK. Compared to the state-of-the-art experiments, requiring zero gravity or large…