The exploration of the inundated prehistoric landscapes on our coastal shelves is one of the great challenges remaining to archaeology. In Britain and North West Europe over the last two decades, the results of dedicated research projects, commercial work carried out in preparation for marine infrastructure and community archaeology programmes have transformed our understanding. In May 2021, the Society of Antiquaries and the ERC research project “Europe’s Lost Frontiers” are co-hosting a two-day event to bring researchers together to present the results of new research. Day 1 ( 6 May) will be dedicated to the results of the Europe’s Lost Frontiers project. Day 2 (7 May) will bring together other researchers, focussing on the British Isles and the North Sea but including new research elsewhere.