United will become the first airline to connect Denver and Rome nonstop.
The carrier will operate daily seasonal service next year between May 1 and Sept. 24. United will fly a Boeing 787-9 Dreamliner configured with business, premium economy and economy cabins.
United will fly four European routes from its Denver hub next summer. Rome will join London, Frankfurt and Munich. United's other transoceanic destination from Denver is Tokyo Narita.
Rome is one of United's eight new daily routes from Denver, joining six domestic destinations and one in Canada.
The carrier will fly daily summer seasonal routes in 2025 from Denver to Pensacola, Fla.; North Bend, Ore.; and Wilmington, N.C. Those three routes begin in May and wind down in August or October.
United will launch year-round service from Denver next spring to Buffalo, N.Y.; Peoria, Ill.; Redding, Calif.; and Regina, Saskatchewan. Peoria launches March 30, with the other three routes following in May.