INTRODUCTION
For several decades, but with a movement that has recently accelerated, the terms tourism, environment and heritage are marked by a convergent dynamic of their fields of application. From mass tourism we are gradually moving towards ecotourism and green tourism, from traditionally more strictly cultural tourism we are turning more and more towards a more global approach to heritage.
Tourism, a complex phenomenon, is expressed through many variations. It stands out as one of the major industries in the world. (Breton, J.M., 2011). Despite its great value, it is considered as a harmful activity for the environment and cultural heritage, this is not always the case, tourism can discover, build and protect a tangible and intangible heritage, and therefore interferes in current protection and heritage processes.
Mediterranean tourism is still characterized by strong competition centered mainly on a seaside model. It does not sufficiently value the cultural and environmental potential of the region.
This option could, however, place the Mediterranean tourist regions in a complementary position, in the image of what is outlined in the offers made by some tour operators who are confined to the northern shores of the Mediterranean, alternating visits to archaeological sites, beauties natural or rich cities of their historical and cultural heritage.
Cultural discovery tourism has been practically one of the oldest and best known forms of tourism for decades. It is an important way to celebrate, preserve and promote the heritage of a state. Since the formalization of the cultural tourism discourse in the late 1970s, the notion of cultural tourism that respects the environment and local populations has emerged by jointly asking the question of tourism and culture (Lazarotti, 2010 ).
Cultural heritage: means of building a nation
Algeria was the place of development of the first Mediterranean cities and civilizations of the Antiquity, in particular the Carthaginians then obviously the Romans. The scientific literature is very rich on this subject. We must obviously mention some very famous sites and among the most striking remains of the Roman period: Tipaza, Timgad, Djemila, so many sites that reflect the importance of the integration of the current Algerian space to the Roman Empire to whom he gave great names, including writers, politicians, including an emperor and one of the greatest theologians of Roman Christendom, St. Augustine. The slow decomposition of the Roman Empire and the deterioration of the climatic conditions, from the 4th and 5th century of our era pushed many peoples from Eastern Europe to advance towards the more favorable lands of the Mediterranean area. The territory of Algeria is no exception and it is the Vandals who settle in the 5th century and Augustine as bishop of Hippo, the current Annaba dies during the siege of his city in 430.
The domination of kings vandals is of short duration since as of the 6th century, it is the Byzantine empire which resumes foot in North Africa, contributing to restore the Roman cities. But the vandal destructions have substantially emptied the plains and the countryside. The Byzantines succeeded in the 7th century, the raids of the conquerors converted to Islam, with some islands of Christian resistance mostly refugees in the mountains, as in the Aures. The rapid success of the conversion of the local populations leads to the fusion of the current Algerian space in an Arab-Muslim ensemble that the Turkish invasions come to attach to the Ottoman Empire by favoring the blossoming of an original built heritage in the form rich palaces, mosques, forts, etc. Indeed, the discovery of this great history of Algerian heritage, has been the subject of the heritage of several sites and listed on the list of heritage of UNESCO and other national and international organizations.
If today's Algeria is the result of a long history, of a cultural melting pot, it is also, just like most other countries around the Mediterranean, a space that has been strongly and lastingly marked by transformations that human societies have made on the natural environment.