static pages for authenticated users only

I'm in the process of converting a site to Drupal that has a large number of (mostly html) pages that are restricted to members. I'd like to have it so any link to one of these pages forces a check that the person is logged in on drupal and then serves the page as normal (and all of the subsequent graphics etc.)

I've put this restricted tree into the drupal directory and have been fiddling with .htaccess permissions, but is there any way short of registering every individual page as drupal files in the database?

Thanks for any pointers.

Chris