We all see dozens of articles targeted at the basic SEO strategies for daily use, but there’s a second set of techniques which we rarely see addressed: the needs of a mature website. If your site is five, ten, fifteen years old or older, and regularly publishes content, chances are good that you have pages on your own website that you haven’t even checked on in years.

You might want to blow the dust off of some of those. After all, you’re paying for the server space to host them and they’re all very well-indexed by the spiders by now. As time goes on, various little instances of webpage rot begin to creep in. here’s something to keep in mind if you do revisit those back-roads off the beaten brush:

Dead links. The page was there five years ago, but now it isn’t. This is especially frustrating in the case of dynamic content, blogs, and just active websites. In some cases, the content is still there, but the website you’re linking to might have gone through a major overhaul since then and changed the way it serves old articles, such as changing the URL’s arguments (the parts that come after the question mark). Even a difference of one character can break a link.

Links to blacklisted sites. This is the case where not only is the content you used to link to not there any more, but the whole domain has gone expired and been bought up by a new party, who now hosts adult, spammy, or illegal content. That causes the search engine spiders such as Googlebot to come along and penalize you for linking to it – and here you had no idea! Check your old blog posts for these ticking time bomb links.

Promoting your greatest hits. Remember that great post you made in 2007 that got you to the front page of Digg.com and bumped your traffic? How about a follow-up? You’re probably still getting the occasional visitor from that. You could drop in an update on that post encouraging visitors to check out other content on your site, you could see about making a static URL page there so it’s more prominent, you could revisit the subject to see if lightning strikes again, and you could post your most-visited content in the sidebar throughout your site. Capitalizing on past work beats having to do new work.

Managing comments on old threads. Anyplace where visitors can leave feedback is a potential place for both profit and trouble. You might want to consider instituting a policy of closing comment threads that are more than two years old, if your content is time-sensitive. At least, you should check the links left in comments to make sure they’re not dead or linking to blacklisted content, or making ‘no-follow’ tags for comment URLs. Some comments can also be harming your page by listing irrelevant keywords or gibberish.

Changing needs. Did you post a review of some kind of media, such as movies or games? Did you have a blog post comment on a news story? That content might be so old and irrelevant now that you’d be better off removing it, or updating it for the times. Or you might have keywords optimized right for 2003, but since then the relevant keywords for your target topic have changed. You might even need to update the web page code itself for the changing browser standards.

Now all we need is for Discovery channel to start a show called “This Old Website!”