If you mean hosting multiple Durandal SPAs in one page there's some discussion on this here.
You'll probably want to host the Durandal SPAs in separate iframes otherwise you'll probably have problems with routing.
However, if you mean hosting different Durandal apps from one ASP.NET MVC site then it's easy: just serve them from different HTML files. Areas have nothing to do with Durandal really. They're more for a 'normal' web application.