Tehran is considered the most liberal city in Iran and younger generations flock from all over the country for acceptance and education. Though settlement in the area dates back over 7,000 years, Tehran itself was demolished and rebuilt from scratch in the 1920s so has little to offer in ancient architecture, but it makes up for that with its fantastic museums, galleries, restaurants, cafés and walking trails. Highlights on a Tehran Free Walking Tour include the National Museum, Golestan Palace, the Grand Bazaar, the Azadi Monument, Milad Tower and Saad Abad Complex. Probably the biggest tourist trawler in the city is the Treasury of National Jewels. Accessed through the front doors of the central bank, it houses jaw-dropping examples of jewelry belonging to former royalty now serving as a reserve for the national currency. You shouldn't miss Imamzadeh Saleh Shrine, which is one of the oldest and most famous, dating back to the early 13th century.