Abstract: An in-line, all terrain skate apparatus for retrofit to a conventional ski boot. The skate apparatus generally comprises a frame member having front and back ends and defining a longitudinal axis extending between the front and back ends. Rotatably connected to the frame member are a plurality of wheels which are disposed in horizontal, linear alignment. Rigidly connected to the front end of the frame member is a toe connector which is sized and configured to receive a toe portion of the ski boot and rigidly secure the toe portion to the frame member when the toe portion is inserted thereinto. Pivotally connected to the rear end of the frame member is a heel connector which is sized and configured to be engageable to a heel portion of the ski boot and releasably secure the heel portion to the frame member when engaged thereto.