Theearth’ssurfacehaschangeddramaticallyovertime.Itsfragilecrusthasfoldedandbuckledandfaulted,andnowherearethesenaturalforcesmoreevidentthanintheworld’sgreatmountains.Inthisepisode,viewersventuretothefootofMountEverest,beforeexploringthesmallerbutmucholdermountainrangesofCentralAustralia,andthentheAndes,thelongestmountainrangeonearth.