Tokyo- Japan Tokyo officially Tokyo Metropolis is one of the 47 prefectures of Japan. It is located on the eastern side of the main island Honshū and includes the Izu Islands and Ogasawara Islands. Tokyo Metropolis was formed in 1943 from the merger of the former Tokyo Prefecture and the city of Tokyo. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family.

The Tokyo Metropolitan government administers the twenty-three special wards of Tokyo, each governed as a city, that cover the area that was the city of Tokyo as well as 39municipalities in the western part of the prefecture and the two outlying island chains. The population of the special wards is over 8 million people, with the total population of the prefecture exceeding 13 million.

New York - United States New York is the most populous city in the United States and the center of the New York metropolitan area, which is one of the most populous metropolitan areas in the world. New York City has a significant impact on global commerce, finance, media, culture, art, fashion, research, education, and entertainment. As host of the United Nations Headquarters, it is also an important center for international affairs. The city is often referred to as New York City or the City of New York, to distinguish it from the state of New York, of which it is a part.

Located on a large natural harbor on the Atlantic coast of the Northeastern United States, New York City consists of five boroughs: The Bronx, Brooklyn, Manhattan Queens, and Staten Island. With a population of 8.4 million distributed over a land area of just 305 square miles (790 km2),New York is the most densely populated major city in the United States. As many as 800 languages are spoken in New York, making it the most linguistically diverse city in the world. The New York metropolitan area's population is the United States' largest, estimated at 19.1 million people distributed over 6,720 square miles (17,400 km2). The New York metropolitan area is also part of the most populous combined statistical area in the United States, containing 22.2 million people as of 2009 Census estimates.

Sao Paulo - Brazil São Paulo is the largest city in Brazil, the largest city in the southern hemisphere, and the world's7th largest metropolitan area. The city is the capital of the state of São Paulo, the most populous Brazilian state. The name of the city honors Saint Paul. São Paulo exerts strong regional influence in commerce and finance as well as arts and entertainment. São Paulo is considered an Alpha - World City. The city has many landmarks, such as the Paulista Museum, the neo-gothic Metropolitan Sé Cathedral, the São Paulo Museum of Art (MASP), the Monumento às Bandeiras (Monument to the Bandeiras) and Niemeyer's Ibirapuera Bienal Complex; and more recently the Octávio Frias de Oliveira Bridge (Estaiada Bridge) in the South Side. Paulista Avenue, in Midtown, is the city´s most important financial center.

The city also lies at the center of the heavily urbanized São Paulo metropolitan area, with an estimated 19,889,559 people in 2009 over 7,944 square kilometers (3,067.2 sq mi), is the largest metropolitan area in the nation. São Paulo metropolitan area is ranked as the second most populous in the Americas. A famous nickname for the city is "Sampa." São Paulo is also known for its unreliable weather, the size of its helicopter fleet, architecture, gastronomy, and multitude of sky scrapers.

Incheon- South Korea Incheon, officially the Incheon Metropolitan City, is South Korea's third or fourth largest metropolis, after Seoul and Busan, and tied with Daegu. As the largest seaport on the west coast and home to the country's largest airport, Incheon International Airport, Incheon is South Korea's most important transport hub. In the 21st century, Incheon has transformed into a global business hub centered around the high-tech and futuristic Songdo International City, which is home to South Korea's tallest building, the 305m super tall Northeast Asia Trade Tower.

Human settlement at the location goes back to the Neolithic. In modern times Incheon became important because its location on an estuary made it a good harbor; when the port was founded in 1883, the city, called Jemulpo at the time had a population of only 4,700. Incheon is now home to over 2.5 million people and under the control of one of the two free economic zone authorities in Korea, aimed at attracting foreign investment; the city aims to turn itself into a financial and corporate hub along with the Busan- Jinhae Free Economic Zone Authority.

Mexico City- Mexico Mexico City is the Federal District capital of the Mexico and seat of the federal powers of the Mexican Union. It is also the largest city in Mexico as well as the second largest city in the Americas and the world's third largest metropolitan area by population, after Seoul and Tokyo. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole. Mexico City is the most important political, cultural, and financial center in the country.

Mexico City is one of the most important financial centers in North America which is located in the Valley of Mexico, a large valley in the high plateaus at the center of Mexico, at an altitude of 2,240 meters (7,350 ft). The city consists of sixteen boroughs. The 2009 estimated population for the city proper was around 8.84 million people, and has a land area of 1,485 square kilometers (573 sq mi). According to the most recent definition agreed upon by the federal and state governments, the Mexico City metropolitan area population is 21.2 million people, making it the largest metropolitan area in the Americas and the fifth largest agglomeration in the world.