In the cool uplands of Nuuanu, on a 3.7-acre patch of sacred land dedicated in 1865 -- and never surrendered to the United States -- stands the Royal Mausoleum, the final resting place of King Kalakaua, Queen Kapiolani, and 16 other Hawaiian royals. Only the Hawaiian flag flies over this grave, a remnant of the kingdom. Allow about an hour for your visit.