Iran is divided into 31 provinces, known as ostan, each with its own unique culture, geography, and history. The provinces vary in size and population, with Tehran being the most populous and serving as the capital city. Other notable provinces include Isfahan, famous for its stunning architecture, and Fars, known as the historical heartland of Persia. Each province is further divided into counties, districts, and villages, facilitating local governance. The provinces are essential for administrative purposes and play a significant role in the country's economy, culture, and social structure, reflecting the diverse heritage of Iran.