1961- amériquecentrale amériquedusud biographies biography calderas california centralamerica coe colombia colombie denny descriptionandtravel descriptionsetvoyages ecologyinart ejércitodeliberaciónnacional(colombia) ejércitodeliberaciónnacional(colombie) exhibitions f formations(geology) geology greg hansen history inart kidnappingvictims motorcycletouring mototourisme mountaineers nature(aesthetics) onwin pictorialworks rockclimbing scotland southamerica travelheggstad unitedstates victimesd'enlèvement voyagesheggstad yosemitevalley