Paper incorporating a wide elongate impermeable element with regions at least partially exposed at one surface of the paper at two sets of windows at spaced locations has its windows formed by two sets of raised portions on the support surface of the papermaking machine. A first set of raised portions has a width transverse to the machine direction in which the paper travels during manufacture which is narrower than the width of the elongate element. A second set of raised portions has a width transverse to the machine direction which is at least equal to the width of the elongate element. During manufacture of the paper the elongate element is brought into contact with both sets of raised portions, with edges of the elongate element being supported by the second set of raised portions.