Our seas and oceans are home to a tremendous amount of archaeological sites and artefacts. These invaluable witnesses to history are often difficult to locate, and even then experts are still faced with the question of whether to conserve them in situ or bring them to the surface. The SASMAP project has developed tools and technologies that will help solve both conundrums. The value of underwater cultural heritage no longer needs to be proven. According to UNESCO estimates, some 3 million ships wrecks are spread across the world’s ocean floors. And that’s without counting submerged heritage sites: In Denmark alone, where the ‘UNESCO Scientific Colloquium on the Access to Underwater Cultural Heritage’ will take place from 8 to 9 June 2016, around 20 000 sites can be found. It therefore comes as no surprise that the National Museum of Denmark, as coordinator of the SASMAP project, set out to help archaeologists to better map and protect these hidden treasures.