The authors have produced ultrathin epitaxial graphite films, typically composed of 3 graphene sheets, grown on the (0001) surface of 6H-SiC. These films exhibit remarkable 2D electron gas (2DEG) behavior, characterized by low-temperature conductance spanning a range of localization regimes. The films show weak localization characteristics, with estimated elastic and inelastic mean free paths. At low fields, the Hall resistance is linear up to 4.5 T, indicating n-type carriers with a density of \(10^{12} \, \text{cm}^{-2}\) per graphene sheet. The most highly ordered sample exhibits Shubnikov-de Haas oscillations, suggesting the potential for a new quantum Hall system. The high-mobility films can be patterned using conventional lithographic techniques, and modulation of the film conductance using a top-gate electrode has been demonstrated. These findings suggest the potential for electronic device applications based on nano-patterned epitaxial graphene (NPEG), with the possibility of large-scale integration. The results highlight the scientific promise of ultrathin epitaxial graphite films for nanoelectronics, including coherent devices, energy efficiency, and easy integration with molecular devices.The authors have produced ultrathin epitaxial graphite films, typically composed of 3 graphene sheets, grown on the (0001) surface of 6H-SiC. These films exhibit remarkable 2D electron gas (2DEG) behavior, characterized by low-temperature conductance spanning a range of localization regimes. The films show weak localization characteristics, with estimated elastic and inelastic mean free paths. At low fields, the Hall resistance is linear up to 4.5 T, indicating n-type carriers with a density of \(10^{12} \, \text{cm}^{-2}\) per graphene sheet. The most highly ordered sample exhibits Shubnikov-de Haas oscillations, suggesting the potential for a new quantum Hall system. The high-mobility films can be patterned using conventional lithographic techniques, and modulation of the film conductance using a top-gate electrode has been demonstrated. These findings suggest the potential for electronic device applications based on nano-patterned epitaxial graphene (NPEG), with the possibility of large-scale integration. The results highlight the scientific promise of ultrathin epitaxial graphite films for nanoelectronics, including coherent devices, energy efficiency, and easy integration with molecular devices.