The study reports the observation of stable magnetic skyrmions in ultrathin Pt/Cu/MgO nanostructures at room temperature and zero applied magnetic field. Using high lateral resolution X-ray magnetic circular dichroism microscopy (XMCD-PEEM), the researchers imaged the chiral Néel internal structure of the skyrmions, attributing it to the strong Dzyaloshinskii-Moriya interaction (DMI) revealed by spin wave spectroscopy. Micromagnetic simulations and numerical models were used to identify the physical mechanisms governing the size and stability of the skyrmions. The results demonstrate that the DMI and magnetostatic interactions play crucial roles in the stability and size of the skyrmions, with lateral confinement also being important. This work opens new avenues for the design of devices based on the manipulation of magnetic skyrmions.The study reports the observation of stable magnetic skyrmions in ultrathin Pt/Cu/MgO nanostructures at room temperature and zero applied magnetic field. Using high lateral resolution X-ray magnetic circular dichroism microscopy (XMCD-PEEM), the researchers imaged the chiral Néel internal structure of the skyrmions, attributing it to the strong Dzyaloshinskii-Moriya interaction (DMI) revealed by spin wave spectroscopy. Micromagnetic simulations and numerical models were used to identify the physical mechanisms governing the size and stability of the skyrmions. The results demonstrate that the DMI and magnetostatic interactions play crucial roles in the stability and size of the skyrmions, with lateral confinement also being important. This work opens new avenues for the design of devices based on the manipulation of magnetic skyrmions.