SEO, URI's and routing.... Best practices?

[eluser]Aken[/eluser]
It will NOT affect your search engine rankings as long as engines cannot find the alternate URL. Yes, duplicate content is bad, but if you do not incorporate the "duplicate" page as part of your website, no one will ever know it's there.

You could also set up a route to block that particular URI, and redirect it to a 404 page, if you wanted additional peace of mind. But the biggest thing is to never create links or references to duplicate content on your website.