The effect of bottom topography H on the barotropic transport through a periodic gap in a basin with large-scale bottom topography is studied. The results obtained generalize previous findings for the case of a zonal channel (Wang and Huang, 1995; Krupitsky and Cane, 1994). An asymptotic approximation is found for the zonal transport on a β-plane when all f/H isolines are blocked by the solid boundaries. It is shown that to leading order, the transport through the gap (i) is independent of friction similar to a western boundary current; (ii) is inversely proportional to R, the range of values of f/H that exist on both parts of the solid boundary. The transport depends on the latitude of the equatorward side of the gap, but not on the poleward one. The transport is forced by a mean wind in the area poleward of the equatorward side of the gap and in two remote forcing regions discussed in the text.