How do you refer to continents in the abstract? I've been trying to figure out how to refer to continents as a concept as opposed to specific continents themselves. For example, I know that the continent of Europe would be translated as 欧洲大陆, or 非洲大陆.

But how do I refer to continents as a whole, countable thing. Like "He went to five continents this summer?"
这个夏天他去了五个洲。(闲聊天)/这个夏天他去了五大洲（较官方）。