Alaska and Delta are fierce competitors in Seattle, and Alaska's new widebody airplanes are raising the stakes. Kent Nishimura/Getty Images

Alaska Airlines launched its first-ever flight to Europe on Tuesday.

It's part of a broader push into long-haul flying from Seattle, a market Delta dominates.

Alaska plans to connect Seattle to at least a dozen long-haul markets by 2030.

Seattle-Tacoma International Airport has been a chessboard between Alaska Airlines and Delta Air Lines for years.

Alaska Airlines is the hometown carrier, with a dominant domestic network and a loyal local customer base that gives it roughly half of the airport's market share. Delta Air Lines has a smaller domestic footprint, but has spent more than a decade becoming the biggest international competitor from Seattle.

But Alaska is now pushing into that territory.

The airline launched its first-ever flight to Europe on Tuesday, flying a Boeing 787 Dreamliner 11 hours from Seattle to Rome.…