Delta will begin flights between its Minneapolis-St. Paul hub and Copenhagen in May.
The thrice-weekly seasonal route follows the onset of a codeshare agreement in late September between Delta and SAS, Copenhagen's largest carrier.
SAS on Sept. 1 moved from the Star Alliance to SkyTeam, of which Delta is a member.
Delta said the codeshare will provide its customers access via SAS to more than 80 connecting destinations beyond Copenhagen.
Delta will be the lone carrier flying between Minneapolis and Copenhagen and will serve the route with Airbus A330-300 aircraft equipped with business class, premium economy and economy cabins.
Copenhagen will be one of two new routes for Delta from Minneapolis next summer, joining Rome. Other European destinations the carrier serves from Minneapolis are London, Dublin, Paris, Amsterdam and seasonal summer service to Reykjavik.
Minneapolis will be Delta's second launching point to Copenhagen, joining summer seasonal service from New York JFK.
Minneapolis-Copenhagen is a part of a buildup that will make Delta's 2025 summer transatlantic schedule its largest ever. The carrier plans to fly more than 700 weekly flights to 33 transatlantic destinations next summer.
Other new routes will include Detroit-Dublin, Boston-Milan, Atlanta-Brussels, Atlanta-Naples, Boston-Barcelona and JFK to the Sicilian city of Catania.
Also, Delta announced that it plans to resume service between Los Angeles and Shanghai next June. The carrier will fly the route thrice weekly, competing against China Eastern and United, Cirium flight schedule data shows.
Delta will operate the route with Airbus A350 planes, equipped with business, premium economy and economy cabins.
Delta last flew LAX-Shanghai in February 2020, suspending the route when Covid-19 broke out.
LAX will join Detroit and Seattle as Delta gateways to Shanghai.