<Tr> <Th_colspan="2"> Site history </Th> </Tr> <Tr> <Th> In use </Th> <Td> 1899--present </Td> </Tr> <Table> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> Pearl Harbor, U.S. Naval Base </Td> </Tr> <Tr> <Td_colspan="2"> U.S. National Register of Historic Places </Td> </Tr> <Tr> <Td_colspan="2"> U.S. National Historic Landmark District </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> Aerial view of Pearl Harbor, Ford Island in center . The Arizona memorial is the small white dot on the left side above Ford Island . </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> Nearest city </Th> <Td> Pearl City, Hawai ʻi </Td> </Tr> <Tr> <Th> Area </Th> <Td> 13,107 acres (5,304 ha) </Td> </Tr> <Tr> <Th> Built </Th> <Td> 1911 </Td> </Tr> <Tr> <Th> NRHP reference #</Th> <Td> 66000940 </Td> </Tr> <Tr> <Th_colspan="2"> Significant dates </Th> </Tr> <Tr> <Th> Added to NRHP </Th> <Td> 15 October 1966 </Td> </Tr> <Tr> <Th> Designated NHLD </Th> <Td> 29 January 1964 </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Pearl Harbor, U.S. Naval Base </Td> </Tr>

When was the naval base at pearl harbor built