ESN Sweden is the intermediate level of ESN, that is, in between the local sections and ESN International. ESN Sweden does a lot of work focused on improving the lives of the students they serve through their National Board, the National Coordinators and the various Committees.
Amongst other things, every semester (usually once in November and once in April) ESN Sweden organizes the ESN Sea Battle, an international cruise between Stockholm (Sweden) and Tallinn (Estonia). This is one of the biggest events in Northern Europe with thousands of participants from three countries!
You can read more about ESN Sweden on their webpage.