 A feature of maritime archaeology is that despite all the material that is lost, there are occasional rare examples of substantial survival, from which a great deal can be learned, due to the difficulties often experienced in accessing the sites.There are those in the archaeology community who see maritime archaeology as a separate discipline with its own concerns (such as shipwrecks) and requiring the specialized skills of the underwater archaeologist.Others value an integrated approach, stressing that nautical activity has economic and social links to communities on land and that archaeology is archaeology no matter where the study is conducted.