A penetration-proof glass panel window structure for building installations, including - a rectangular window frame, - a first panel and at least one further panel, each including a facade element and a rectangular panel frame with an axis of rotation, the facade elements being arranged on the panel frame and having an outer surface directed towards a building exterior and an inner surface directed towards a building interior, the panel frames being arranged with the axes of rotation horizontally in the window frame and the panels (1, 2) in a closed position having a window surface oriented parallel to the window frame, closed except for function-related gaps and covering the window frame, - a mounting structure for fixing the window frame in a building structure, and - a movement device for opening and closing the panels (1, 2), wherein - the first panel has a first facade element and is arranged horizontally at the top of the window frame, - each further panel has a respective second facade element and is arranged horizontally below the first panel on the window frame, and - the first facade element and the second facade element each have an inner visible area and an edge area surrounding the inner visible area, characterised in that - the first facade element and the second facade element each have, on the inner surface, an inner pane and a central pane connecting the inner pane to the respective facade element (11, 21), which are connected in the visible region to form a penetration-proof laminated safety glass, the inner pane being larger than the central pane and smaller than the respective facade element (11, 21), - the edge region of the first facade element is completely covered on the inner surface with a first reinforcing frame, - the edge region of the second facade element is completely covered on the inner surface with a second reinforcing frame and in the upper edge region with an additional cover strip, - the panel frame of the first panel has a reinforcing strip arranged at the top of the panel frame, - the window frame has reinforcing inserts which, in the closed position of the panels (1, 2), are arranged to reinforce an edge surrounding the window surface, and - a mounting frame is arranged as a mounting structure for the window frame in the building structure. - a rectangular window frame, - a first panel and at least one further panel, each including a facade element and a rectangular panel frame with an axis of rotation, the facade elements being arranged on the panel frame and having an outer surface directed towards a building exterior and an inner surface directed towards a building interior, the panel frames being arranged with the axes of rotation horizontally in the window frame and the panels (1, 2) in a closed position having a window surface oriented parallel to the window frame, closed except for function-related gaps and covering the window frame, - a mounting structure for fixing the window frame in a building structure, and - a movement device for opening and closing the panels (1, 2), - the first panel has a first facade element and is arranged horizontally at the top of the window frame, - each further panel has a respective second facade element and is arranged horizontally below the first panel on the window frame, and - the first facade element and the second facade element each have an inner visible area and an edge area surrounding the inner visible area, - the first facade element and the second facade element each have, on the inner surface, an inner pane and a central pane connecting the inner pane to the respective facade element (11, 21), which are connected in the visible region to form a penetration-proof laminated safety glass, the inner pane being larger than the central pane and smaller than the respective facade element (11, 21), - the edge region of the first facade element is completely covered on the inner surface with a first reinforcing frame, - the edge region of the second facade element is completely covered on the inner surface with a second reinforcing frame and in the upper edge region with an additional cover strip, - the panel frame of the first panel has a reinforcing strip arranged at the top of the panel frame, - the window frame has reinforcing inserts which, in the closed position of the panels (1, 2), are arranged to reinforce an edge surrounding the window surface, and - a mounting frame is arranged as a mounting structure for the window frame in the building structure.