The Polish Maritime Museum in Gdansk participated in the EU project MACHU aiming at creation of a system of location, making information on European subaqueous maritime cultural heritage available and dissemination of it. 7 EU countries co-operated in the project. The Wood Technology Institute contributed to research on durability of small oak wood samples submerged in the sea. The samples were considered bioindicator of changes. The outline of research in the project is presented below.