Researchers have observed stationary current vortices, or whirlpools, in monolayer graphene at room temperature using a scanning nitrogen-vacancy (NV) magnetometer. These vortices, which resemble hydrodynamic flow patterns, were detected in devices with varying sizes, disappearing as the device size increased. The vortices were observed in both electron- and hole-dominated transport regimes but not near charge neutrality, where the vorticity diffusion length decreases. The study confirms predictions of the hydrodynamic model, showing that transport in graphene can exhibit hydrodynamic behavior, characterized by collective carrier interactions rather than traditional diffusive or ballistic transport. The observed vortices are attributed to a reduction in vorticity diffusion length near charge neutrality, and the results highlight the power of local imaging techniques in revealing exotic mesoscopic transport phenomena. The study also demonstrates that hydrodynamic transport can occur at room temperature in high-mobility materials where the momentum-relaxing scattering length exceeds the carrier-carrier scattering length. The findings suggest that hydrodynamic transport is governed by the collective behavior of interacting carriers, leading to transport features such as viscosity and turbulence. The research provides insights into the nature of electron transport in graphene and opens new avenues for exploring hydrodynamic effects in two-dimensional materials.Researchers have observed stationary current vortices, or whirlpools, in monolayer graphene at room temperature using a scanning nitrogen-vacancy (NV) magnetometer. These vortices, which resemble hydrodynamic flow patterns, were detected in devices with varying sizes, disappearing as the device size increased. The vortices were observed in both electron- and hole-dominated transport regimes but not near charge neutrality, where the vorticity diffusion length decreases. The study confirms predictions of the hydrodynamic model, showing that transport in graphene can exhibit hydrodynamic behavior, characterized by collective carrier interactions rather than traditional diffusive or ballistic transport. The observed vortices are attributed to a reduction in vorticity diffusion length near charge neutrality, and the results highlight the power of local imaging techniques in revealing exotic mesoscopic transport phenomena. The study also demonstrates that hydrodynamic transport can occur at room temperature in high-mobility materials where the momentum-relaxing scattering length exceeds the carrier-carrier scattering length. The findings suggest that hydrodynamic transport is governed by the collective behavior of interacting carriers, leading to transport features such as viscosity and turbulence. The research provides insights into the nature of electron transport in graphene and opens new avenues for exploring hydrodynamic effects in two-dimensional materials.