. >> and for mary ann ettinger, proud of her lakota heritage. >> almost made me cry when i saw them runast, there is something that pulls at my heart. >> soon over a ridge top the first buffalo break the horizon, barely visible at first but then the whips crack. and the cowboys holler is the way they always have. >> ah get up there! get up there! come on. come on. >> and the vast empty plains come to life. the ground itself shaking from the thundering hooives. hooves. a sound so ominous it terrifies a herd of elk and sends them scattering. if the scene seems familiar, no wonder, it was here in the very valley where the star studded cast filmed how the west was won. and for these modern cowboys even with some modern help trying to herd the buffalo on their native turf and not always getting their way. >> head them out head 'em out,. >> get out at a here. >> was a heart-pounding thrill. buffalo are fears and fast, able to outrun a man in short bursts. >> this is terry sorenson's first time in the roundup. >> what is it like? >> very exciting, race along, wind flying, buffalo, everything l