Tokyo, officially Tokyo Metropolis, one of the 47 prefectures of Japan, has served as the Japanese capital since 1869. As of 2014, the Greater Tokyo Arearanked as the most populous metropolitan area in the world. The urban area houses the seat of the Emperor of Japan, of the Japanese government and of the National Diet. Tokyo forms part of the Kantō region on the southeastern side of Japan's main island, Honshu, and includes the Izu Islands and Ogasawara Islands. Tokyo was formerly named Edo when Shōgun Tokugawa Ieyasu made the city his headquarters in 1603. It became the capital after Emperor Meiji moved his seat to the city from Kyoto in 1868; at that time Edo was renamed Tokyo. Tokyo Metropolis formed in 1943 from the merger of the former Tokyo Prefecture  and the city of Tokyo. Tokyo is often referred to as a city but is officially known and governed as a "metropolitan prefecture", which differs from and combines elements of a city and a prefecture, a characteristic unique to Tokyo.

The 23 Special Wards of Tokyo were formerly Tokyo City. On July 1, 1943, it merged with Tokyo Prefecture and became Tokyo Metropolis with an additional 26 municipalities in the western part of the prefecture, and the Izu islandsand Ogasawara islands south of Tokyo. The population of the special wards is over 9 million people, with the total population of Tokyo Metropolis exceeding 13.8 million. The prefecture is part of the world's most populous metropolitan area called the Greater Tokyo Area with over 38 million people and the world's largest urban agglomeration economy. As of 2011, Tokyo hosted 51 of the Fortune Global 500 companies, the highest number of any city in the world at that time. Tokyo ranked third (twice) in the International Financial Centres Development Index. The city is home to various television networks such as Fuji TV, Tokyo MX, TV Tokyo, TV Asahi, Nippon Television, NHK and the Tokyo Broadcasting System.

Nagoya is the largest city in the Chūbu region of Japan. It is Japan's fourth-largest incorporated city and the third-most-populous urban area. It is located on the Pacific coast on central Honshu. It is the capital of Aichi Prefectureand is one of Japan's major ports along with those of Tokyo, Osaka, Kobe, Yokohama, Chiba, and Kitakyushu. It is also the center of Japan's third-largest metropolitan region, known as the Chūkyō metropolitan area. As of 2015, 2.28 million people lived in the city, part of Chūkyō Metropolitan Area's 10.11 million people. It is also one of the 50 largest urban areas in the world.

a seaport and naval base on the Malabar Coast of southwestern India, in the state of Kerala; population 254,500 (est. 2009).

a city in southwestern Japan, on the southern coast of the island of Honshu; population 1,144,572 (2007). It was the target of the first atom bomb, which was dropped by the US on August 6, 1945, and resulted in the deaths of about one third of the city's population of 300,000. This, with a second attack on Nagasaki three days later, led to Japan's surrender and to the end of World War II.

Kagoshima is the capital city of Kagoshima Prefecture at the south western tip of the island of Kyushu in Japan, and the largest city in the prefecture by some margin. It has been nicknamed the "Naples of the Eastern world" for its bay location (Aira Caldera), hot climate, and emblematic stratovolcano, Sakurajima. The city was officially founded on April 1, 1889.

Nagasaki is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. The city's name means "long cape" in Japanese. Nagasaki became a centre of colonial Portuguese and Dutch influence in the 16th through 19th centuries, and the Hidden Christian Sites in the Nagasaki Region have been recognized and included in the UNESCO World Heritage List. Part of Nagasaki was home to a major Imperial Japanese Navy base during the First Sino-Japanese War and Russo-Japanese War.

During World War II, the American atomic bombings of Hiroshima and Nagasaki made Nagasaki the second and, to date, last city in the world to experience a nuclear attack (at 11:02 a.m., August 9, 1945 'Japan Standard Time (UTC+9)').

As of 1 March 2017, the city has an estimated population of 425,723 and a population density of 1,000 people per km2. The total area is 406.35 km2 (156.89 sq mi).

Nagasaki is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. The city's name means "long cape" in Japanese. Nagasaki became a centre of colonial Portuguese and Dutch influence in the 16th through 19th centuries, and the Hidden Christian Sites in the Nagasaki Region have been recognized and included in the UNESCO World Heritage List. Part of Nagasaki was home to a major Imperial Japanese Navy base during the First Sino-Japanese War and Russo-Japanese War.

During World War II, the American atomic bombings of Hiroshima and Nagasaki made Nagasaki the second and, to date, last city in the world to experience a nuclear attack (at 11:02 a.m., August 9, 1945 'Japan Standard Time (UTC+9)').

As of 1 March 2017, the city has an estimated population of 425,723 and a population density of 1,000 people per km2. The total area is 406.35 km2 (156.89 sq mi).

Seoul, officially the Seoul Special City, is the capital and largest metropolis of South Korea. With surrounding Incheon metropolis and Gyeonggi province, Seoul forms the heart of the Seoul Capital Area, home to roughly half of the country's population. Seoul is ranked as the fourth largest metropolitan economy in the world and is larger than London and Paris.

Strategically situated on the Han River, Seoul's history stretches back over two thousand years, when it was founded in 18 BCE by the people of Baekje, one of the Three Kingdoms of Korea. The city was later designated the capital of Korea under the Joseon dynasty. Seoul is surrounded by a mountainous and hilly landscape, with Bukhan Mountainlocated on the northern edge of the city. As with its long history, the Seoul Capital Area contains five UNESCO World Heritage Sites: Changdeok Palace, Hwaseong Fortress, Jongmyo Shrine, Namhansanseong and the Royal Tombs of the Joseon Dynasty. More recently, Seoul has been a major site of modern architectural construction – major modern landmarks include the N Seoul Tower, the 63 Building, the Lotte World Tower, the Dongdaemun Design Plaza, Lotte World, Trade Tower, COEX, and the Parc1 Tower. Seoul was named the 2010 World Design Capital. As the birthplace of K-pop and the Korean Wave, Seoul received over 10 million international visitors in 2014, making it the world's 9th most visited city and 4th largest earner in tourism.

Today, Seoul is considered a leading and rising global city, resulting from the South Korean economic boom - commonly referred to as the Miracle on the Han River - which transformed it into the world's 7th largest metropolitan economy with a GDP of US$635.4 billion in 2014 after Tokyo, New York City and Los Angeles. International visitors generally reach Seoul via AREX from the Incheon International Airport, notable for having been rated the best airport for nine consecutive years (2005–2013) by the Airports Council International. In 2015, it was rated Asia's most livable city with the second highest quality of life globally by Arcadis, with the GDP per capita (PPP) in Seoul being $39,786. Inhabitants of Seoul are faced with a high cost of living, for which the city was ranked 6th globally in 2017. Seoul is also an extremely expensive real estate market, ranked 5th in the world for the price of apartments in the downtown center. With major technology hubs centered in Gangnam and Digital Media City, the Seoul Capital Area is home to the headquarters of 15 Fortune Global 500 companies, including Samsung, LG, and Hyundai. Ranked sixth in the Global Power City Index and Global Financial Centres Index, the metropolis exerts a major influence in global affairs as one of the five leading hosts of global conferences. Seoul has hosted the 1986 Asian Games, 1988 Summer Olympics, 2002 FIFA World Cup, and more recently the 2010 G-20 Seoul summit.