THE LIMESTONE PLATEAU SHAPED BY KARSTING
The region of Altamura stands on a limestone plateau known as the Murge, consisting of carbonate rock from the Cretaceous era shaped by the phenomenon of karsting. The landscape has been modelled by centuries of erosion caused chiefly by rainwater, whose carbon dioxide content has a dissolving action on calcium carbonate. Karsting produces such natural phenomena as sink-holes, deep ridges known locally as "lame", canyons, potholes, wells and grottoes, the latter often lending themselves to human habitation in the prehistoric and historical eras. The Alta Murgia, seemingly so barren and inhospitable, is in fact a unique environmental eco-system, being the last surviving example of Mediterranean pseudo-steppe in peninsular Italy and one of the most important anywhere in the Mediterranean. Its rocky, scrub-filled expanses, its garigue-like bush, its grassy steppes and now rare patches of oak forest host some 1,500 species of plant life whose unquestioned stars are the myriad varieties of wild orchid.
Roughly 80 species of bird populate the Alta Murgia, the substantial group of birds of prey including in particular the only nesting population of lesser kestrels in peninsular Italy. The area designated as the Alta Murgia National Park with its unique landscape, flora and fauna is remarkable for its countless farmhouses, livestock pens and tracks, dry stone walls and watering holes.