Chicago, IL (ORD) to Tangier, Morocco (TNG).  $567 round-trip, including all taxes. Select February and March travel dates only.

Iberia Airlines is back at it, they offered similar prices to these Moroccan cities back in November but they disappeared quickly.

Flights to Marrakech (RAK) and Casablanca (CMN) departing from other U.S. cities including Miami and Boston, are being offered for a similar price. Below are some other great fares we found:

Boston-Marrakech $527 rt / incl. tax.
Boston-Tangier $527 rt / incl. tax.
Miami-Marrakech $577 rt / incl. tax.
Chicago-Casablanca $569 rt / incl. tax.

Be warned most of the return flights include long layovers in Madrid, so keep that in mind before booking.