KLM will be offering a Cyber Monday Flash Sale for flights between the U.S. and Europe and we have a preview of those offers for you. The fares start as low as $669 all in between Chicago and Bucharest and go up from there. These can only be booked on Monday December 1 for travel between December 29 and March 27. They also require a 7 day minimum stay. You can book these special fares via this link on December 1st only.