Amusement device comprising: • a central shaft having a substantially vertical axis (A1), said central shaft comprising a base structure ; • a plurality of arms , coupled to said central shaft , each of said arms (3a - 3d) being rotatable around a relevant arm axis (A2), provided with one or more vehicles having seats for users of said amusement device , preferably arranged at both the ends of said arms (3a - 3d); • a gear system for rotating said plurality of arms (3a - 3d), the gear system comprising: - a gear motor (M) coupled to a first gear , to rotate said first gear ; - a plurality of second gears , one for each arm of said plurality of arm, coupled to said first gear so that rotation of the first gear drives in rotation said second gears (72a - 72d), the rotation of said second gears (72a - 72d) causing rotation of each arm (3a - 3d) around the relevant arm axis; wherein the gear system is configured so that the angular speed of said arms (3a - 3d) is substantially identical for all the arms; wherein said first gear is directly meshing with said second gears (72a - 72d), or it is coupled to said second gears (72a - 72d) via one or more secondary gears, wherein said central shaft comprises one or more movable portions , that are movable with respect to said base structure , said arms being coupled to said movable portions , and wherein said gear motor (M), said first gear and said second gears (72a - 72d) are mounted on one of said movable portions of said shaft . • a central shaft having a substantially vertical axis (A1), said central shaft comprising a base structure ; • a plurality of arms , coupled to said central shaft , each of said arms (3a - 3d) being rotatable around a relevant arm axis (A2), provided with one or more vehicles having seats for users of said amusement device , preferably arranged at both the ends of said arms (3a - 3d); • a gear system for rotating said plurality of arms (3a - 3d), the gear system comprising: - a gear motor (M) coupled to a first gear , to rotate said first gear ; - a plurality of second gears , one for each arm of said plurality of arm, coupled to said first gear so that rotation of the first gear drives in rotation said second gears (72a - 72d), the rotation of said second gears (72a - 72d) causing rotation of each arm (3a - 3d) around the relevant arm axis; - a gear motor (M) coupled to a first gear , to rotate said first gear ; - a plurality of second gears , one for each arm of said plurality of arm, coupled to said first gear so that rotation of the first gear drives in rotation said second gears (72a - 72d), the rotation of said second gears (72a - 72d) causing rotation of each arm (3a - 3d) around the relevant arm axis; wherein the gear system is configured so that the angular speed of said arms (3a - 3d) is substantially identical for all the arms; wherein said first gear is directly meshing with said second gears (72a - 72d), or it is coupled to said second gears (72a - 72d) via one or more secondary gears, wherein said central shaft comprises one or more movable portions , that are movable with respect to said base structure , said arms being coupled to said movable portions , and wherein said gear motor (M), said first gear and said second gears (72a - 72d) are mounted on one of said movable portions of said shaft . <EOS>