Istanbul, which is the largest city in Turkey and acting as a bridge between two continents, plays a vital role in internal and external trade. Istanbul is also a cultural and educational centre of the country. The ferry transportation between continents has a great importance in the city transportation. Approximately 20 million people live in this region and suffer from traffic jam. In Istanbul, people use alternative ways to save their time. The best alternative is marine transportation. As a transportation method, marine transportation is naturally risky. Accidents, that have caused many pecuniary losses and intangible damages have occurred during the history of transportation with ferries. This study aims to find out critical points which show dangerous areas according to data of accidents, in ferry transportation in Istanbul. Specialists may criticize these points and suggest solutions to avoid effects of ferry-line accidents in future. Specialists create certain maps to help public corporations so that they can benefit from these resulted maps when they decide to create new lines. İstanbul has lots of ferry lines and many of people use these lines; so accidents are unavoidable. This paper will be a guidebook for new lines and it also helps reduce any of losses related to ferry transportation.a This study deals with issues related to ferry accidents and selection of right line in Istanbul. Creating the right line is always a difficult task for the public corporations. This study is hoped to provide different perspective for corporations so that they can select the most likely effective ways easily.