Yn ystod 2018 roeddem yn dathlu arfordir Cymru a'r môr, ac yn ystod Blwyddyn y Môr cynhaliwyd Ras Cefnfor Volvo; daethom yn genedl ail-lenwi gyntaf y byd; a chynhaliwyd dathliad o'r iaith Gymraeg a Diwylliant gyda’r  Eisteddfod ym Mae Caerdydd. Cynhaliwyd amrywiol ddigwyddiadau hefyd ledled Cymru, o Ŵyl Gerflunio ar draeth y Gŵyr i greu anghenfil môr enfawr 20 metr o Aberteifi ac ymgyrch Glanhau Traethau Cymru Gyfan Cadwch Gymru'n Daclus. Roedd 2018 hefyd yn flwyddyn ar gyfer cynyrchiadau theatrig arfordirol gyda The Tide Whisperer gan National Theatre Wales a Nawr yr Arwr/ Now the Hero gan Marc Rees.
2018 was a celebration of Wales’ coastline and routes to the sea and during Year of the Sea Wales successfully hosted the Volvo Ocean Race for the first time; became the world’s first refill nation; and a celebration of Welsh language and Culture was held at the Eisteddfod in Cardiff Bay. A variety of events were also held across Wales from the Gower Beach Sculpture Festival to the creation of a giant 20-metre long sea-faring monster from Cardigan and the Keep Wales Tidy All Wales Beach Clean.  2018 was also a year for immersive coastal theatrical productions with National Theatre Wales’ The Tide Whisperer and Marc Rees’s Now the Hero/Nawr yr Arwr.