At the risk of starting a debate, it is my most humble opinion that the horse head in the bed scene is the most famous scene to most people. Keeping that in mind, it is my guess, that when discussing location scenes for the Godfather, the interior shot where the horse's head scene took place, is the location given for Woltz's mansion, not the exterior scenes where Woltz is talking with Tom around the pools.

Also thank you for the clarification of Falaise and Guggenheim being the same.