How can I make a site and all its content inaccessible in Edit and Visit?

I tried deactivating the site and its child nodes, but the content is still available from links with the nid-parameter (http://somesite.com/?nid=1234). Is it possible to make the entire site inaccessible somehow, or should I just add a redirect in the masterpage for all page requests?

Are you sure you didn't have "edit" open in another tab? Requests against an unpublished node should return a 404.

Indeed I did. Facepalm!