The ESN Sea Battle is an international cruise brought to you by ESN Sweden. The cruise takes place twice a year, once per semester, usually in November and April. Each event has around 2100 international participants, and the officially participating countries are ESN Sweden, ESN Denmark, ESN Norway, ESN Estonia, ESN Latvia and ESN Lithuania.
During the cruise some of the free program on-board is karaoke, speed dating, treasure hunts, salsa lessons, competitions, etc. The cruise has three dance floors and also the ferry company organizes shows aboard.
During the trip, the students from Sweden, Denmark and Norway have the possibility to visit Tallinn, Estonia for half a day where ESN Estonia is responsible for sightseeing tours. The participants from Estonia, Latvia and Lithuania have the possibility to visit Stockholm, Sweden for half a day where ESN Sweden is responsible for sightseeing tours.