Delta attacks Star Alliance at Chicago ORD with low fares to Athens, Greece in the $541 to $572 range, available from next week to May 15, even some dates during December holidays. This deal is available every day of the week and almost every date.
United/Star Alliance has these same fares available through several airlines including Air Canada, Lufthansa, and Swiss.
You can reduce the prices even more checking Momondo.com meta-search for lower ticket prices through online travel agencies (OTAs). I found ORD-ATH $508 on my date search with United and Swiss flights and $495 for next May with Air Canada flights (see below).
Delta Airlines Chicago ORD – New York JFK – Athens, Greece ATH – Amsterdam AMS – Chicago ORD
$571.76 round trip Sun Sep 4 – Thu Sep 15
You can also book an overnight layover in Amsterdam on some dates.
United Airlines / Air Canada OTA ticket through Momondo.com search.
Chicago ORD – Montreal YUL – Athens ATH – Montreal YUL – Chicago ORD
$494.86 round trip TravelMerry.com ticket Sat May 6 – Mon May 15
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