We report on a scanning tunnelling microscope equipped with a piezoelectric inertial slider micropositioner. For any orientation, the proposed device allows an approach down to the tunnelling distance from the tip. The approach process is fully automated by a personal computer that generates the driving signals. Continuous motion at a speed of 5 mm s-1 and single-step advancement down to 50 Å are obtained. The microscope, due to its mechanical symmetry and rigidity, can operate with atomic resolution, using a few stage vibration isolation stacks. The instrument can easily be modified to operate as an atomic force microscope with a fibre-optic-interferometer displacement sensor.