Airlines are adding new routes and making a bold bet on continued strong demand for travel

Building on strong bookings this summer, American Airlines said Thursday it will add three new European destinations next summer and revive another international route that it last flew in 2019. The announcement comes one day after Delta Air Lines said it will expand service to China later this year. American said that next summer it will add flights to Copenhagen, Naples and Nice, France — all new destinations for the airline — from Philadelphia.