<Table> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> Hearst San Simeon Estate </Td> </Tr> <Tr> <Td_colspan="2"> U.S. National Register of Historic Places </Td> </Tr> <Tr> <Td_colspan="2"> U.S. National Historic Landmark </Td> </Tr> <Tr> <Td_colspan="2"> California Historical Landmark #640 </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> The Casa Grande is the 60,645 square - foot centerpiece of Hearst Castle . </Td> </Tr> <Tr> <Td_colspan="2"> Show map of California Show map of the US Show all </Td> </Tr> <Tr> <Th> Nearest city </Th> <Td> San Simeon, California, United States </Td> </Tr> <Tr> <Th> Area </Th> <Td> More than 90,000 sq ft (8,400 m) </Td> </Tr> <Tr> <Th> Built </Th> <Td> 1919 - 1947 </Td> </Tr> <Tr> <Th> Architect </Th> <Td> Julia Morgan </Td> </Tr> <Tr> <Th> Architectural style </Th> <Td> Mediterranean Revival, other late 19th and 20th century Revivals </Td> </Tr> <Tr> <Th> NRHP reference #</Th> <Td> 72000253 </Td> </Tr> <Tr> <Th> CHISL #</Th> <Td> 640 </Td> </Tr> <Tr> <Th_colspan="2"> Significant dates </Th> </Tr> <Tr> <Th> Added to NRHP </Th> <Td> June 22, 1972 </Td> </Tr> <Tr> <Th> Designated CHISL </Th> <Td> April 28, 1958 </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Hearst San Simeon Estate </Td> </Tr>

Why did the hearst family donate hearst castle