Iran , also known as Persia , officially the Islamic Republic of Iran , is a sovereign state in Western Asia It is bordered to the northwest by Armenia, the de facto Nagorno-Karabakh Republic, and Azerbaijan; to the north by Kazakhstan and Russia across the Caspian Sea; to the northeast by Turkmenistan; to the east by Afghanistan and Pakistan; to the south by the Persian Gulf and the Gulf of Oman; and to the west by Turkey and Iraq. Comprising a land area of 1,648,195 km2 (636,372 sq mi), it is the second-largest country in the Middle East and the 18th-largest in the world. With 78.4 million inhabitants, Iran is the world's 17th-most-populous country. It is the only country with both a Caspian Sea and an Indian Ocean coastline. The country's central location in Eurasia and Western Asia, and its proximity to the Strait of Hormuz, make it of great geostrategic importance.Tehran is the country's capital and largest city, as well as its leading cultural and economic center.

The Achaemenid Persian Empire was founded by Cyrus the Great around 550 B.C.E., who went by the title of King of Kings (Shahanshah). Although the Persian Empire came to an inglorious end at the hands of Alexander the Great in 330 B.C.E., it had a lasting legacy on the subsequent development of world civilizations and future empires. Indeed, the Persian Empire was a pivotal empire because it was the first true empire that set the standard of what it meant to be an empire for future ones.

The Persian Empire existed at a unique time in history, when most of the oikumene, or civilized, settled, populated world was concentrated in or near the Middle East. As a result, the Persian Empire, which dominated most of the Middle East, ruled over a greater percentage of the world’s population than any other empire in history. Indeed, in 480 B.C.E., the empire had a population of approximately 49.4 million people, which was 44 percent of the global population at that time. The Persian Empire was the first empire to connect multiple world regions, including the Middle East, North Africa, Central Asia, India, Europe, and the Mediterranean world. It jumpstarted the concept of empires in places like Greece and India.

The Persian Empire ushered in a period of harmony and peace in the Middle East for two hundred years, a feat that has seldom been replicated.

Iran is divided into five regions with thirty one provinces each governed by an appointed governor. The provinces are divided into counties , and subdivided into districts and sub-districts.

Tehran , with a population of around 8.1 million (2011 census), is the capital and largest city in Iran. It is an economical and cultural center in Iran, and is the hub of the country's communication and transport network

The country's second largest city,Mashhad , has a population of around 2.7 million (2011 census). It is the capital of Razavi Khorasan Province, and is a holy city in Shia Islam, as it is the site of the Imam Reza Shrine. About 15 to 20 million pilgrims visit the Shrine of Imam Reza every year

Isfahan, with a population of around 1.7 million (2011 census), is Iran's third largest city and the capital of Isfahan Province. It was also a former capital of Iran, and contains a wide variety of historical sites; including the famous Image of the World Square, Siose Bridge, and the sites at the Armenian district of New Jolfa. It is also home to the 5th largest shopping mall in the world, namely Isfahan City Center.

The fourth major city of Iran,Karaj , has a population of around 1.6 million (2011 census). It is the capital of Alborz Province, and is situated 20 km west of Tehran, at the foot of the Alborz mountains. It is a major industrial city in Iran, with large factories producing sugar, textiles, wire, and alcohol.

Tabriz, the capital of East Azerbaijan Province, is considered the second industrial city of Iran . With a population of around 1.4 million , it is the fifth major city of Iran, which had been the second-largest until the late 1960s. It is one of the former capitals of Iran, the first capital of the Safavid Empire, and has also been proven extremely influential in the country’s recent history.

Shiraz, with a population of around 1.4 million (2011 census), is the sixth major city of Iran. It is the capital of Fars Province, and was also a former capital of Iran. The area was greatly influenced by the Babylonian civilization, and after the emergence of the ancient Persians, soon came to be known as Persis. Persians were present in the region since the 9th century BC, and became rulers of a large empire under the reign of the Achaemenid Dynasty in the 6th century BC. The ruins of Persepolis and Pasargadae, two of the four capitals of the Achaemenid Empire, are located around the modern-day city of Shiraz.