We report on the thermodynamic, structural and dynamic properties of a recently proposed Deep Eutectic Solvent (DES), formed by choline acetate and urea at the stoichiometric ratio 1:2, hereinafter indicated as acetaline. Acetaline, although melting at ca. 40 °C, can be easily supercooled in its liquid state at sub-ambient conditions. The existence of a crystalline phase has been detected, together with the glass-liquid transition at -50 °C. Synchrotron high energy X-ray scattering experiments provide the experimental data for supporting a Reverse Monte Carlo analysis to extract structural information at atomistic level. This exploration of acetaline's liquid structure reveals the major role played by hydrogen bonding in determining interspecies correlations: both acetate and urea are strong hydrogen bond acceptor sites, while both the choline hydroxyl and urea act as HB donors. All acetaline moieties are involved in mutual interactions, with acetate and urea strongly interacting through hydrogen bonding, while choline being involved mostly in van der Waals mediated interactions. Such a structural situation is mirrored by the dynamic evidences obtained by means of 1 H NMR techniques, that show how urea and acetate species experience higher translational activation energy than choline, fingerprinting their stronger commitments into the extended hydrogen bonding network established in acetaline.