The eastern boundary runs through Istanbul (which is quite distinct), the Dardanelles and Bosphorus and thence up the Urals.

The western boundary would be around the shores of Scotland and Ireland. There are some outlying islands such as the Azores, Iceland, the Faroes etc associated for cultural and political reasons.

I would say Cyprus, not Iceland, is the real anomaly. Much as I like Iceland, it is an outlier in every sense of the word.

I know some people argue that Europe is geographically Asia. Personally I would have divided Asia up into at least three continents.