Watch Movies2Watch. In 1970, Warren Harding and Dean Caldwell set out to climb Early Morning Light, better known as Dawn Wall, in Yosemite National Park. Arguably the most controversial climb in the park's history, due to multiple storms and a rescue attempt by the Yosemite Service. The climb thrust the event into the media spotlight, creating a controversy within the local climbing community. In this short documentary, Warren Harding himself recounts the climb.