Tourism is one the most demanded industry today. People from different corners of the world travel to different countries in order to see distinguished traditions, nature, culture, art, etc. Local cuisine, folk music, traditions, historical-cultural monuments, architectural buildings are a part of culture. Architectural-historical buildings are one the most attractive cultural monuments for tourists from different parts of the world. In Azerbaijan there are more than 6500 monuments of architecture.
We can classify the monuments in Azerbaijan according to their function, architectural style, school of architecture, period of construction, etc.
As Azerbaijan is a country situating in between Europe and Asia, we can easily observe oriental and western motives in the decorations. Mostly, we can vary two main architectural style in Azerbaijan as Eastern or oriental style, and Western or European style of architecture.
Geographically we can distinguish 4 different school of architecture in Azerbaijan as Eastern School (Shirvan school), Northern school, Western School, Southern School. Each school of architecture mostly vary by the construction materials, architectural style, and the most important, for the ornaments used in decoration of the monument.
Azerbaijan is a very ancient place where people settled from the first human life. Archaeological excavations and ancient buildings are the most important evidences for the antiquity of Azerbaijan.
The area is full of ancient monuments. Starting from the first period of human life, in the territory of Azerbaijan were found out the monuments. Historically, we can classify cultural-historical monuments in the territory of Azerbaijan to the different parts based on the states ruled in the territory of Azerbaijan:
Pre-historical monuments belonging to the pre-historic times as menhirs, dolmens, cromlechs, ancient caves made by people and other cyclopic monuments.
Median period, Albanian period, Arabic Caliphate period, Mongolian Period, Great Turkic Empires period, Khanate period, Russian Empire period, The first democracy period, Soviet times, post-Soviet and modern Azerbaijan Democracy period.
Each period has uniqueness. There is different classification according to the period as Nizami's period monuments (monuments of XII century),early medieval centuries, middle ages, Oil boom period (end of XIX'th - beginning of XX's centuries), etc.

The next classification of cultural-historical monuments are their functions. We can see here very simple classification as mentioned below:
1. Religious monuments (fire worshippers or Zoroastrian temples, Albanian churches, mosques, etc.)
2. Memorial buildings (ancient gravel stones, mausoleums)
3. Caravanserais (ancients guest houses)
4. State buildings (Palaces)
5. Defensive constructions (fortresses, city walls, towers, etc.)
6. others ("hamams", "ovdans", etc)

Importance of the monuments, first is its importance for culture, as they are sample for our culture. Second, being a mirror of our history they are very valuable for our history.
During archaeological excavations archaeologists find out the ruins of ancient buildings, regarding to which, they value the development of the population and the lifestyle of the people living in the territory of Azerbaijan. We can be proud of our land that is rich with cultural-archaeological specimens and  monuments.
In my paper I would like to speak not only about the value of the monuments, but at the same time I would like to speak about the protection and conservation of the monuments.
Today, there is a very prominent list of monuments by UNESCO which are known as Cultural heritage. Some monuments of Azerbaijan are also included to that list. The most important among them is the symbol of Azerbaijan "Maiden's Tower" that was included to the world heritage list of UNESCO in 2000 in a line with walled city (XII century), Mohammed Mosque (XI century) and Shirvanshahs' Palace of XV century. The monuments included to the list of UNESCO are considered to be "The monuments of Universal Value" and protected by Government.
Monuments vary by their value as well as the monuments of local value and the monuments of national value. The government protects the cultural-historical monuments with some conservation and restoration work. there are some buildings that are totally destroyed are reconstructed by the Government according to different resources, manuscripts and paintings, as Bibi Heybat mosque, Shamakha Juma Mosque, etc.
Nowadays the most important problem is a lack of conservation and some changes in the construction during restoration work. Some buildings after their restoration lost their previous form. Mostly, in Soviet times the monuments were restored very rudely. Cement was used during restoration, as a sample "Ateshgah" fire-worshippers temple, which is now under restoration by our Government.

Even our government takes care of the monuments in the territory of Azerbaijan, there are some monuments/buildings that are out of interest. Mostly, the monuments situated in the regions, forests, etc.
Here we can say that tourism has advantages and disadvantages for the cultural-historical monuments. First, the monuments those are interested and visited by tourists are "in the list". Other monuments that not very acceptable to the tourists are "out of interest". But, they can be easily damaged when a lot of tourists visit it. They should be protected from tourists' affect because of the sustainable development of cultural and historical tourism. The tourists should be informed and the monuments should be protected by the museum "watchers", cameras, generally, the security system should be strengthen. 

Concluding my paper I would like to add that, all the monuments in our territory, even remains and ruins, not depending on their period of construction, architectural style, function, have very essential values for us.  We should protect the monuments that preserved our history and culture. We must take care of them as we learn our history through them. To protect them and pass it to the next generation is our duty.