A towing system comprises towers arranged relative to a skiing surface; a pulley on each tower; and a motor effecting rotation of at least one pulley. A cable passes along the pulleys and forms a closed loop between the towers. A towing element is coupled to the cable for towing a user along the skiing surface. The system features a number of innovations. A rigid member is arranged to hold a tower upright and has tension therein for tensioning the cable. A support assembly supporting the pulley is arranged for pivotal motion relative to the tower for adjusting a plane within which the pulley rotates. Guide rollers properly guide the cable over each pulley. The pulley comprises angular track portions which are removable independent of one another. Panels partially enclosing the support assembly are movable into a position to define a platform for supporting objects and people thereon during maintenance.