In and just east of the Namib Desert of Namibia, the oldest
desert in the world, some of the most impressive but desolate
landscapes of southern Africa may be experienced. At a certain
point, some 100km inland, this desert gradually turns into
steppe. Among the many impressive "Inselberge" and plateaux
dominating that contact zone is a tranquil valley that bisects a
large sandstone plateau (Figure 2). Located in this valley is
the rock-art site of Twyfelfontein (1 in Figure 1), a really
magical place. Its enchanting atmosphere is not only created by
the attractive colours of the red and yellow sandstones and its
many imposing rock formations, but also and especially by the
hundreds of mainly animal engravings that have been pecked into
numerous rock surfaces by prehistoric peoples. Often, gigantic
boulders are grouped close together, forming inviting labyrinths
composed of towering blocks, creating narrow passages, quiet
alcoves and stark shadows. And when you go through such a
passage, you are often taken by