Major Europe sale is back!!! Flights starting at $434 RT, generally on American Airlines (though other airlines are matching), travel August - March, excluding Christmas/NYE**. Jump on this deal quickly
**We also found two flights to Barcelona over Christmas/NYE from IAD ($497 RT) or LAX ($600 RT!!! So, other destinations may be available too.
Washington DC/Chicago/Boston/New York/Los Angeles/San Francisco, USA
Barcelona/Madrid/Ibiza/Palma de Mallorca/Valencia/Bilbao, Spain
Booking: use Google Flights to find a working date, then proceed to book with Momondo for cheapest fares. Found first on Secret Flying.