A ski comprising a front runner (1), a centre runner (2) and a rear runner (3); the runners (1, 2, 3) connectable together to form a longitudinal running surface, the centre runner further comprising a locking mechanism (4) operable to urge the front and rear runners into engagement with the centre runner. Part (5, 7) of the locking mechanism is concealed within the body of the ski and the remaining part (12, 13) is positioned in-between the ski boot (16) bindings so that when the ski boot is clamped into the bindings it forms a protective canopy over the locking mechanism and the assembly takes on the appearance of a one piece ski When the ski is dismantled it can be carried in a case compatible with automated luggage handling systems and inside automobiles without the need for a roof rack.