A million years ago the great ice sheets carved two immense, spectacular valleys our of solid rock. Both valleys would come to be inhabited by man over thousands of years. One valley, Yosemite, was in time designated as a National Park. The other, equally as beautiful and just north of Yosemite, is called Hetch Hetchy and, since 1923 when the O’Shaughnessy Dam was built across its narrow access, remains under 300 feet of