4. University of California, Berkeley

The roots of the University of California go back to the gold rush days of 1849, when the drafters of the state's constitution required the legislature to 'encourage by all suitable means the promotion of intellectual, scientific, moral and agricultural improvement' of the people of California.
The university that was born nearly 20 years later -- on March 23, 1868 -- was the product of a merger between the College of California (a private institution) and the Agricultural, Mining, and Mechanical Arts College.
Among other things, the university is credited with the isolation of the human polio virus and the discovery of all artificial elements heavier than uranium. Eighteen members of the Berkeley faculty have been awarded Nobel Prizes for these and subsequent discoveries, as well as in literature and economics.