this summer i'm going to barcelona, amsterdam, prague, and lisbon. i've been checking flights for landing in barcelona and departing amsterdam to come back home. it's running around $1300 right now, which is a little high for me. last year i booked a similar trip for around 800.

so anyway i tried searching a round trip to barcelona and it has a layover in amsterdam. it's only $900!! so why not just get off there and start my vacation in AMS then eventually make my way to barcelona when i want to catch my return flight? is there any penalty for doing this? would delta void my return flight or anything?

if there's no problem, then i'm booking the flight tonight. it's like $400 cheaper to book a round trip to barcelona than a multi-city flight.