Abstract: Disclosed is a magnetically controlled base isolation system that in a simple, practical, and cost effective way significantly reduces the lateral forces transmitted to buildings, bridges, and other structures during earthquakes. It comprises sliding bearings that are constructed with steel elements, elastomeric O-rings, and permanent magnets; contain a pressurized fluid; and slide over electricity-conducting metallic base plates. It also comprises permanent magnets disposed at the periphery of the metallic base plates. The pressurized fluid carries the bulk of the vertical load supported by each bearing, minimizing thus the magnitude of the frictional forces that resist the bearings' sliding. The motion of the permanent magnets in the sliding bearings over the electricity-conducting base plates generates damping forces that reduce the bearings' relative displacements to practical levels.