A gas bearing system comprising two opposing substantially parallel bearing surfaces (2, 3) and at least one gas duct (6) for supplying gas through an orifice (7) to the bearing gap (5) between the bearing surfaces (2, 3). At least one of the bearing surfaces (2, 3) is provided with at least one cavity (8, 9) extending over 0.3 mm.sup.2 to 3 mm.sup.2 of the at least one bearing surface (2, 3). The content of the cavity (8, 9) may be between 0.3 mm.sup.3 and 4 mm.sup.3. The gas duct (6) may supply gas to the cavity (8) through an orifice (7) in the wall of the cavity (8).