Norwegian Airlines via ShermansTravel offers Norwegian Airlines Roundtrip Flights to Europe from select cities in the U.S. for as low as $309.80. (On the ShermansTravel landing page, click on "Norwegian.com" in the main paragraph to see this offer.) That's the lowest price we could find for select routes by $78, although we saw fares for $37 less in December. This price is based on departure on September 18 from Boston, MA, (BOS) with arrival in Oslo, Norway, (OSL) and return on September 26. This sale includes routes to Copenhagen, Denmark, (CPH); Stockholm, Sweden, (ARN); and more. Book this travel deal by May 31.

All prices, dates, and booking details were valid at the time of publication.