SeaDataNet (SDN) is a major pan-European infrastructure for ocean and marine data and gives access to high quality multidisciplinary data (physical oceanography, marine chemistry, geology, bathymetry, geophysics, and biology). The SDN portal offers different services: discovering, visualisation, access and data downloading as well as data products and metadata services. It is active since 2006, it involves more than 100 data centers and it makes available more than 2 million datasets. It also develops and governs common standards for metadata and data formats, common vocabularies and quality flags as well as standard software tools. Marine data centers that want to promote and distribute their data through the SeaDataNet infrastructure can take advantage of a long term data preservation, tools for data management and all the other services offered. The marine stakeholders can use the marine data resources and products available and thus they are invited to visit the web portal at address: https://www.seadatanet.org.