Via Loyalty Traveler, you can fly round-trip to cities like Amsterdam, Barcelona, Dublin, London, Madrid, and Zurich from Charlotte, Dallas, and Philadelphia for between $442 and $578. I checked and also found cheap flights from Newark!
For instance, you can fly round-trip Newark to Amsterdam non-stop for ~$507 on Delta October 6, 2016, to October 13, 2016.
Loyalty Traveler is reporting these cheap Delta fares for September and October 2016 travel, and again in December through May 2017. This includes fares starting at ~$450 round-trip from Charlotte and Dallas to Spain. And ~$525 to Amsterdam, Brussels, London, and more.
Here’s how to find the deal.