A walk underground
The longest caves in the world are in Kentucky, the caves of Mammoth, which are 560 metres long. Other long karstic landscapes are in China, on the Shan plateau; in Australia, in the Nullarbar region; in North Africa, on the Atlas mountain chain; on the Appalachian Mountains in the United States and on Carpathian Mountains in Europe. Karstic landscapes are widely popular in Italy. As well as the already-mentioned Carso region, there are around a hundred caves that are famous for their beauty, dimensions and scientific interest. Moreover, many of these caves are exploited as a tourist resource. The most famous caves are: the cavern of Bossea (Piedmont), the caves of Frasassi (Marche), and the caves of Castellana (Puglia).