SEO and Duplicate URLS

Question

I'm updating a website's menu system and adding SEO urls. I'll have two URLs pointing to a similar resource for a while but only one of them will be rendered on the menu.

Should I leave the old URLs or delete them? If I leave them then google results wont link to 404 pages but they may be considered as spam. Should I redirect them perhaps?

Answer 1

Definitely use a 301 permanent redirection, this is what it's meant for. It'd be nice to keep the old URLs up (with 301 redirects) as long as is practical, for the benefit of people who still have the old URLs bookmarked or something - and Google etc. will know exactly how to deal with them. I highly doubt they'd be considered spam.