Tehran is the capital city of Iran. A bustling metropolis of 14 million people, it is situated at the foot of the towering Alborz mountain range
Tehran is a cosmopolitan city, with great museums, parks, restaurants, warm friendly people. It deserves at least a few days of your Iranian itinerary.
The city can be roughly divided into two different parts - north and south. The northern districts of Tehran are more prosperous, modern, cosmopolitan and expensive while southern parts is less attractive but cheaper. At the time of the Zand dynasty, it was a little town that was significant from a strategic point of view. The first of the Qajar kings, Agha Mohammed Khan, named Tehran as the country's capital in 1778, and most of its growth started during the reign of a subsequent Qajar monarch, Fath-Ali Shah. The castle which Agha Mohammed Khan had built was to contain the new majestic buildings.
At the same time, the city's populace was redoubled. Due to the increasing significance of the city, gates, squares and mosques were built and it was at the time of Nassereddin Shah that the city's master sketch was prepared and modern streets were constructed. Later, huge central squares like Toopkhaneh square (now Imam Khomeini) and quite a few military buildings were built. Even though the Qajar dynasty was in a period of decline, Tehran soon took the shape of a modern city. The structure of large government buildings, new streets, recreation centres, urban service organizations, and academic and methodical centres were started, even as most of the old gates and buildings were destroyed and the city's old architectural fabric replaced by a contemporary one.
A combination of factors make Tehran a pleasant place to visit: The dry climate which is constantly cool (at least in the evenings), the proximity of the mountains, the parks and gardens where flowers blossom all through the year, the alleys of trees in the avenues or even smaller streets, and even the water that runs down from the upper city along deep and wide gutters which look like small rivers during spring. The Alborz range on the north of Tehran, which hosts the highest peak in Iran, provides fantastic conditions for ski lovers in the winter. In winter, the mountain hotels and ski-clubs at Shemshak, and Dizine are full several days a week. Some specialist skiers consider the snow value in northern Tehran to be one of the most excellent in the world. The Azadi Tower has been the longstanding symbol of Tehran. It was constructed to commemorate the 2,500th anniversary of the Persian empire, combines elements of Sassanid and Islamic architecture. The entrance of the tower is directly underneath the main vault and leads into the Azadi Museum on the basement floor. If you want to drool over gold and glitter, take a look at the Treasury of the National Jewels (Ferdosi St, near the corner of Jomhuriyeh Eslami Ave; Metro: Saadi; look for the heavy iron gate and rifle-wielding guards beside the Central Bank). Open Sa, Su, M, Tu 2PM-4:30PM. For the 50,000 rials admission fee you'll get to see a collection of some of the most expensive jewels in the world. Highlights include the world's largest uncut ruby, the world's largest pink diamond (the Sea of Light) and a free standing golden globe made from 34 kilograms of gold and an astounding 51,366 precious stones. An informative 6,000 rials information book is available at the ticket counter, though free tours are given in English.
The National Museum of Iran  has ceramics, stone figures and carvings dating all the way back to around the 5th millennium BC. It is the combination of two museums, the old building dedicated pre-Islamic collection dating from Neolithic all the way to the Sassanid period and the new building dedicated to Iran's 1,400-year Islamic history.
The gigantic Mausoleum of Ayatollah Khomeini (Metro: Haram-e-Motahar) is on the southern edge of the city. The sheer size of the shrine/shopping centre is enough to make the trip worth it. Entrance to the actual mausoleum is free.
Milad Tower, . Milad tower is the fourth tallest tower in the world and 12th tallest freestanding structure in the world, and it is visible from almost everywhere in Tehran. Note that tickets to enter the observation lounge must be reserved well in dvance. to have a meal in a rotating restaurant, 390 meters above earth, you should expect to pay around 200$ per person edit
Jamshidieh Park which is in the Niavaran district at the base of the Kolakchal Mountain, is one of the most picturesque and beautiful parks in Tehran. Mellat Park in Valiasr street is one of the largest recreation areas in the Middle-East. Niavaran Park is one of Tehran's famous and most pleasant public city parks. It is located within the Niavaran district and is situated immediately south of the Niavaran Palace Complex. Additionally there are some large parks called "park-e-jangali" (literally "forest park") around (and some inside) the city which are very popular among the locals for picnic. The most famous one is Chitgar in the west of the city and is accessible via Karaj road.
Museums Tehran has more than 50 museum and 100 art galleries, you can find them in most of Tehran travel guides like Lonely Planet or maps that solds in metro by handy solders in price of 20,000 rials (Less than a dollar) Golestan Palace, , the oldest of the historic monuments in Tehran. The Complex consists of 17 palaces, museums, and Halls.
The Golestan (Rose Garden) citadel is one of mainly visited places in Tehran, which was the Qajars' royal residence, and its garden is an oasis of coolness and peace in the heart of the city. The major building, architecturally unpretentious, houses a museum with objects from the Qajar period in the self-important style of last century. In the Golestan garden, a one-story pavilion to the right and a short distance from the entrance, shelters one of the best organized museums in Tehran. It encloses about thirty showcases presenting almost everything related to Iran, which makes up the critical originality of Iranian life in the a variety of provinces of the country.
Niavaran Palace,is a historical complex which consists of several buildings and a museum. The Sahebqraniyeh Palace, from the time of Naser al-Din Shah of Qajar dynasty, is also located inside the complex.
Kolahstudio-an Art Basement, 
Safir Office Machines Museum,It was founded in 2008 by Frashad Kamalkhani, the museum owner. It includes a collection of early office machines. 
Crown Jewels of Iran, located in Central Bank of Iran. The crown jewels are the largest collection of jewels anywhere in the world. include several elaborate crowns and decorative thrones, tiaras as well as several other more unusual items such as a gemstone globe collected by the Iranian monarchy during its 2,500-year existence.
Sa'd Abad Gallery of Fine Arts, 
Glassware Museum of Tehran, 
Iran's National Rug Gallery,exhibits a variety of Persian carpets from all over Iran, dating from 18th century to present. It has a library that contains 7,000 books 
Reza Abbasi Museum , is named after Reza Abbasi, one of the artists in the Safavid period. The collections of this museum belong to a period from the 2nd millennium BC to the early 20th century. 
Tehran Museum of Contemporary Art,features the works of great artists such as Van Gogh, Pablo Picasso and Andy Warhol. The collection of these paintings were selected by the former Empress Farah Diba. 
Tehran Theater of the Performing Arts (Te'atr e Shahr) Talar Vahdat Theater
National Museum of Iran, 
Darabad Museum of Natural History, Iran's most famous museum for nature and wildlife
Saadabad Palace,is a palace built by the Pahlavi dynasty of Iran in the Shemiran area of Tehran.The complex was first inhabited by Qajar monarchs and royal family in the 19th century.Currently, parts of the Saadabad Palace compound are museums, in which visitors can roam through and look at the rich history of Iran. (Persian site).
Time Museum, Evolution of time-measurement instruments. Located in Farmaniye district, north of Tehran
Money Museum, Coins and banknotes from different historic periods. Located in Mirdamad street.
National Arts Museum, Located in Baharestan district.