Engravings are also associated with a further predominant type of natural topographic feature; routes of access and communication into the wadi. For example, numerous engravings are located in the Maknusa Pass, a wide, sandy valley that represents one of the principal passages into the wadi from the south. Click image above to see a panorama of the Maknusa Pass from part way along its length at the base of the escarpment showing engravings in the foreground. The images cluster together in obvious positions lining both sides of the pass in association with unmistakeable landscape features, particularly at the base of projections of the east and west faces of the escarpment and at the base and summit of inselbergs (isolated, rocky outcrops) in the floor of the pass. Again, images representing several thousand years of activity are concentrated in the same locations. The rock-art sites are intervisible and are positioned so that the engravings face into the pass. Click here to see the landscape of the Maknusa Pass from the summit of an inselberg. Other isolated rocky outcrops visible from this position are also associated with engravings. Deliberate marking of routes of access, and the very visible way in which they were marked, indicates that they were strategically important features during prehistory. Conspicuous display of landscape use and 'ownership' through the engravings may suggest incipient territorial behaviour in relation to these routes.