Alba Light Source 1 article published in JoVE Biology A 3D Cartographic Description of the Cell by Cryo Soft X-ray Tomography Johannes Groen1, Andrea Sorrentino1, Lucía Aballe1, Robert Oliete1, Ricardo Valcárcel1, Chidinma Okolo2, Ilias Kounatidis2, Maria Harkiolaki2, Ana Joaquina Pérez-Berná1, Eva Pereiro1 1MISTRAL beamline, Alba Light Source, Cerdanyola del Valles, Spain, 2Beamline B24, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK Here, a protocol describing the sample preparation and data collection steps required in cryo soft X-ray tomography (SXT) to image the ultrastructure of whole cryo-preserved cells at a resolution of 25 nm half pitch, is presented.