A rotary ski slope comprising an inclined disc which is rotatable about an axis and has a diameter of at least 100 meters. The disc may be divided into a number of concentric rings (1) which are rotatable at different speeds. Means are preferably provided to circulate coolant across the entire under surface of the disc to prevent the snow from melting. The entire surface of the disc is preferably available for skiing with snow conditioning and grooming apparatus (49, 52) being mounted away from the surface, or selectively retractable from the surface. The upper surface of the disc may be non-planar to set up "wave" allowing a variety of skiing conditions to be provided.