Highlighting the value of natural areas is a key element of legitimation for the constraints their protection imposes on certain activities. Travel cost method is used to value the recreational activities of the Port-Cros National Park (France), the first marine Park created in Europe, and currently a marine and terrestrial natural protected area situated on and around the Mediterranean island of Port-Cros. We used a sample of 600 visitors surveyed on several places on site. In order to get appropriate time and travel costs for multi-destination travels, a motivation scale is introduced to weight the costs according to the influence of the Park in the decision to visit the region. The opportunity cost of time is estimated following two methods and the results are discussed. The values obtained for consumer surpluses emphasize the uniqueness of the site which can be related to the insular situation and the fact that a marine protected area accessible to a large number of visitors remains exceptional.