Osaka, which means large hill, has a population of 2.7 million ( was up to 3.1 million in 1965 ) and is the largest component of the Keihanshin ( or Greater Osaka ) Metropolitan Area, the second largest in Japan, and tenth biggest urban area in the world, with 19 million inhabitants.   From the early beginning of the country, Osaka was traditionally considered to be Japan's economic hub, having a major port in the 7th and 8th centuries, and continuing to flourish during the Edo Period (1603-1867), becoming the center for Japanese culture, with Kyoto and Nara in this region.  Our two final stops on this Japan trip are to these two cities. Kyoto was the capital of Japan for more than a millennium, from 794 through 1868. All changed that year when the capital was moved to Edo, which was renamed Tokyo. Osaka was hit hard by U.S. bombing during World War II, particularly just before the end. Reconstruction stimulated population growth. Osaka hosted the World Expo in 1970, and will again