Although multi-drum classical columns are, in general, earthquake resistant despite the lack of any lateral load resisting mechanism except friction, still standing ones are rather vulnerable to future earthquakes as they present many types of damage. To enhance their seismic stability an innovative system is proposed herewith, which consists of an unbonded steel tendon that passes through the centre of the drums of the column and is anchored at the foundation and at the top of the column. During the seismic response, the tendon is elongated due to the rocking of the drums and applies a compressive restoring force to the column increasing its ability to survive strong earthquakes. The restoring force increases as the deformation of the column increases and, in this way, the proposed tendon system results in the “controlled rocking” of the column. The efficiency of the proposed intervention is investigated for the case study of the restoration of the columns of the temple of Pythios Apollo on the Ancient Acropolis of Rhodes in Greece.