A GeoBarrier allows you to prevent spatial searches to find roads on the “wrong” side of a barrier, even if a road there is nearer. A geobarrier can be either lines or polygons.
In the example below, the nearest road is on the Western side of the water, but with the barrier in place (red line), it will find a road on the Eastern side instead.
GeoBarriers will be part of next RW Net 4 release.