Alexandretta is the second largest district of Hatay province surrounded by the Mediterranean at the West and Syria at the East. Although sit was founded around 400 BC, it has started to be urbanized and developed after the mid-19th century. The main reason of this improvement was the positive impacts of the Industrial Revolution on the Eastern Mediterranean port cities. This development process accelerated after the French Mandate period that is started after 1919. This study aims to decipher chronological development and transformation process of the historical urban fabric of İskenderun. The study has been carried out by comparison of old maps and photographs chronologically, their correlation and combination with the information coming from the written sources. In addition to this, field studies have been carried out in order to understand the existence and condition of the cultural values formed the historical urban fabric. The results of the study showed that the urban fabric has changed depending on the change of the administrative statue, social and economic conditions in the transitional period from the Ottoman Empire to the French Mandate. Buildings have been constructed to meet the new need and the city has grown. The city had a rapid industrialization period between 1950 and 1980. The rapid population increase resulted with a dramatic destruction. However, there are still existing structures in the city. In order to reflect a certain time period, these buildings should be preserved.