The City of Honshu is the largest and most populous city in Japan. It is located on the main island of Honshu and is home to many of the country's major cities, including Osaka (5 letters), Hiroshima (9 letters) and Otsu (4 letters). Osaka is the second largest city in Japan and is known for its vibrant culture and nightlife. Hiroshima is a major port city and is famous for being the site of the atomic bombing during World War II. Otsu is a smaller city located on the shores of Lake Biwa and is known for its traditional Japanese architecture.