To take advantage, check out the Norwegian sale page, which lists out the cities they fly out of. Once you've clicked through, they list a lot of one-way prices, showing the best prices available to the destination listed. It's an intuitive system, even if it fails to give you an accurate sense of what roundtrip tickets will cost.
Here's a taste of what you'll find. Flying out of New York City you can get to Stockholm for $283, Oslo for $335.10, and Copenhagen for $394.40. From Boston fly to Oslo for $284.70, Copenhagen for $338.40, and London for $406.40. Fort Lauderdale has flights to Stockholm for $317.50, Oslo for $342.20, Copenhagen for $410.40, Barcelona for $414, and Paris for $424.60.
From the west coast, you can get tickets from Los Angeles to Stockholm for only $360.70, to Oslo for $415.70, to Paris for $566.60, and to London for $589.80.
As always, a word of warning: Tickets go quickly, so these prices might not be there unless you get on it. Also, Norwegian is a budget airline. That means ticket prices can increase quickly with baggage fees and fees for other conveniences. If you truly want to get to Europe on a budget, you'll need to pack light and check ahead for what kind of fees you could be facing.
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