As the capital of Egypt, Cairo is not only the largest city of the country, but also the largest city of Africa and the Arab world. Straddling the Nile River and locating itself in the northeastern part of Egypt, Cairo serves as the political, economic, cultural and transportation center of the Middle East.It is one of the oldest city in the world and one of the few ancient cities in the world that has suffered the least damage from war.

Athens is the capital and largest city of Greece. With a profound history of more than 3,000 years, it is famed as the cradle of western civilization.

Nanjing, referred to as "Ning" and called Jinling and Jiankang in ancient times, is the capital of Jiangsu Province. It boasts the elegant names such as the ancient capital of six dynasties and the capital of ten dynasties. The long history of development and the cultural infiltration of past dynasties have made Nanjing, a famous historical city, surrounded by numerous historical relics with unique charm.

Mexico City, the capital of the United Mexican States, functions as the political, economic and cultural center of the country.

Machupicchu is located in the south of Peru, at the eastern foot of the Andes Mountains. It is one of the world's most famous Inca ruins. Machupicchu is one of the New Seven Wonders of the Modern World, and was declared a World Heritage Site by UNESCO in 1983. Unique location and rich natural and cultural resources have made it one of the most popular tourist attractions in Peru.

St. Petersburg is located in northwestern Russia on the Baltic Sea coast. It is a municipality directly under the Central Government of Russia and an important water and land transportation hub. It is also known as the "Northern Capital" of Russia.