That 50k miles is from any airport serviced by that airline in the continental US to any airport serviced by that airline in the specified region (Western Europe in your case).

That means it cost me the same 50k miles to go to London from Seattle as it does for someone in Boston. Many airlines permit "open-jaw" tickets to Europe. That means you could fly ...oh..as an example Roanoke to Paris and return Madrid to Roanoke.

Of course, you want to read all the fine print in the manual provided with your freequent flyer material. If it is a year or more older, call the airline and ask them to mail you a new one. Many airlines have all their rules and regulations published at their websites.

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