also spelled Teheran, city, capital of Iran, situated on the southern slopes of the Elburz Mountains, 62 miles (100 km) from the Caspian Sea. It lies at an elevation of about 3,800 feet (1,200 m) above sea level between the Jajrud and the Karaj rivers. To the south extends the Central Plateau of Iran. The name Tehran is derived from the Old Persian teh, “warm,” and ran, “place.”

Tehran is the successor to the ancient Iranian capital…