Numbers of properties and districts by county[edit]
The following are approximate tallies of current listings in California on the National Register of Historic Places. These counts are based on entries in the National Register Information Database as of April 24, 2008,[1] and new weekly listings posted since then on the National Register of Historic Places web site.[2] There are frequent additions to the listings and occasional delistings and the counts here are not official. Also, the counts in this table exclude boundary increase and decrease listings which modify the area covered by an existing property or district and which carry a separate National Register reference number.
^The count for Alameda County includes the USS Hornet which was located in Bremerton, Washington, when first listed on the NRHP in 1991, but was moved to Alameda, California, and opened as a museum ship in 1998.