On Monday, San Francisco-based Trust for Public Land donated the Coast Dairies property, which is just north of Santa Cruz, to the U.S. Bureau of Land Management.
The property - which features rolling meadows, redwood forests and panoramic ocean views - was owned for more than a century by two families.
The 5,800 acres of land nearly became a nuclear power plant in the 1970s and luxury homes in the 1990s.
A group of nonprofits helped purchase it in 1998. It took 15 years of legal and political wrangling to get it ready for public use.
Two hiking trails on the land will be open to the public by the end of the year.
(The Associated Press contributed to this report)