‘All of us in a way are climbing blind’

15

(CNN)

Erik Weihenmayer has scaled the seven summits or even endured the violent rapids of the Colorado River– in the dark.< div course=" ad"ad-- impressive"data-ad-text="program">< div id= "ad_rect_atf_02" course=" ad-ad_rect_atf_02 "ad-refresh-default" >