Flying Blue Air France-KLM

AA/UA SFO to Rome $430, DL SFO to Paris $473

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Air France $431 SFO to Paris nonstop

Oneworld/SkyTeam SFO to Frankfurt $479-$494 Aug-May 2018

Delta-SkyTeam $499-$518 August San Francisco to Scotland, Germany, Denmark

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SkyTeam Air Europa $589-$622 Miami–Spain many airports and 25% Flying Blue miles

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Delta/SkyTeam Washington D.C. Mileage Runs, most of Europe in $400s Sep-Dec

Delta-KLM Los Angeles to Dar Es Salaam, Tanzania $884 August to November 2015