It 's about 850 feet tall , 3 miles across , and it grew out of a volcano that erupted in the middle of the bay about 700 years ago .
Also from Mt. Hobson , this is Rangitoto Island , a scenic preserve .
Rangitoto Island 's about 850 feet tall , 3 miles across , and Rangitoto Island grew out of a volcano that erupted in the middle of the bay about 700 years ago .
Also from Mt. Hobson , this is Rangitoto Island , a scenic preserve .