In 1768 what had been the dressing-room of Empress Elizabeth was divided into two parts, one with two windows overlooking the parade-ground, the other with one. In the 1770s the size of the smaller room was further reduced by the construction of a wooden internal staircase and at that time it was finished in the style of the main suite of state rooms. In 1817 the wooden staircase was replaced by a cast-iron one, after which the “Room before the Cast-Iron Staircase” that completes the main enfilade of the Great Tsarskoye Selo Palace (the Catherine Palace) acquired its present name.

Today this fairly small interior has been fully restored: the walls are lined with white damask in carved and gilded frames; a false window glazed with mirrors is placed opposite the real one, visually expanding the space.