Japan’s capital city used to be called Edo. It began its life in 1457, when the warlord Ota Dokan built Edo Castle on the site. A town and city eventually grew around the castle, and in 1603, Japan's military leader made Edo his capital. The emperor's capital was still in Kyoto, in Japan's central part. In1868, Japan's military government collapsed, and the Japanese emperor moved the capital from Kyoto to Edo and renamed the city "Tokyo", which means "eastern capital".
Today's Tokyo is different from Edo 200 years ago. For example, there is no Edo Castle any longer: nowadays, the Imperial Palace is placed on the site. Moreover, the city used to have all wooden buildings, and so fire was constantly a problem: there were over 100 large fires between1603 and 1868. The biggest fire was in 1657, when about 100,000 people lost their lives. Wooden buildings are not common anymore in the glass-and-concrete modern Tokyo. The city also didn't use to be very big: there were 1 million people in the 18th century, but now there are over 35 million. This large population is served by a very large and effective rail and subway system. This is another major change from old Edo: the city didn't use to have any public transportation system at all.
But not everything has changed. For instance, the modern Tokyo district of Odaiba is the centre of Tokyo's recycling industry. Recycling was also important in old Edo, and there used to be laws that forbade throwing trash into rivers: garbage was regularly collected, broken down, and reused. Another thing that hasn't changed, unfortunately, is frequency of earthquakes in the city. There have been five large earthquakes in the city since 1703, and today Tokyo schoolchildren are instructed on preparing for the next one.