It has been a period of many new routes. On June 1st, four launched between Europe and the US. They were: Azores Airlines from Ponta Delgada to New York JFK, Finnair Helsinki-Seattle, Iberia Madrid-Dallas, and Lufthansa Frankfurt-St. Louis. (A fifth, ITA from Rome to Los Angeles, isn't included as it is effectively a continuation from Alitalia days.)

They join multiple others

Multiple other Europe-US routes started around the 1st, such as Delta's Athens-Boston on May 27th and British Airways introducing long-delayed London Heathrow-Portland (Oregon) on June 3rd, the day of writing. On the 4th, United from Palma-Newark will begin, and LOT Polish will take off from Kraków to Newark (last served in September 2010).

To North America more widely, Ethiopian Airlines took off from Lomé to Washington Dulles on June 1st, while SAS started Copenhagen-Toronto on the 2nd. On the 3rd, the Scandinavian carrier is gearing up to take off from Stockholm to Canada's largest city, the same day as WestJet operates its first Edinburgh-Toronto. (Eurowings Discover replaced Lufthansa on Munich-Montréal, but it is only temporary.)

Four new Europe-US routes

Details of the foursome are below. The launch of Azores Airlines to JFK follows the May introduction of United from Newark using B737 MAX 8s. It means that Ponta Delgada-New York has up to 11x weekly flights this summer.

That's a significant number of flights, and the city-pair 68,000 round-trip summer seats for sale, 69% more than the pre-pandemic. While Azores Airlines/United were attracted by the exit of Delta from JFK in September 2019, it'll be interesting to see if the high amount of capacity is sustainable.

1. Azores Airlines: Ponta Delgada-JFK, served up to 4x weekly by the A321neo until September 24th, then 3x weekly during the winter
2. Finnair: Helsinki-Seattle, summer-seasonal; 3x weekly A330-300 flights until October 28th
3. Iberia: Madrid-Dallas, year-round; 4x weekly in the summer, reducing to 3x in winter, all by the A330-200. Supplements fellow oneworld carrier American (1x daily, currently by the B787-9 and later the B777-200ER)
4. Lufthansa: Frankfurt-St Louis, 3x weekly year-round using the A330-300

St Louis' only long-haul route

It has been a long time since St Louis, TWA and then American's former hub, had mainland Europe service. According to the Department of Transportation's T-100 dataset, London Gatwick was the most recent operation, and it ended in October 2003.

Paris CDG ended in September 2001, that fateful month. Therefore, Lufthansa's St Louis service is instrumental in connecting the airport with wider Europe, the Middle East, South Asia, and beyond.

But despite what Lufthansa said in the tweet above, the Missouri airport has had Europe service, albeit not to the mainland, much more recently. Between May 2018 and January 2019, WOW Air linked it to Keflavik and wider Europe. St Louis was one of 17 North American airports served by the defunct operator.