Tokyo is the capital of Japan and it stands at the center of one of the most economically powerful countries in the world. Cars, computers, TV sets, and other items manufactured in Tokyo can be found in every corner of the globe.

Tokyo has been one of the world's largest cities since the seventeenth century. Today it remains one of the most populated cities, with an estimated 12 million people crowded into the eight-hundred-square-mile city boundaries and another 18 million in its surrounding suburbs. Thus, with 30 million people in the greater metropolitan area, almost one-quarter of Japan's 128 million people are within commuting distance of downtown Tokyo.

Built on an island renowned for its earthquakes and volcanic eruptions, Tokyo is prone to major earthquakes, and the city has been devastated many times, most recently in 1923 when the Great Kanto earthquake—and the tidal wave that soon...