Skip URLs That Repeat The Same Path Many Times

[siteadmin]

Google's John Mueller said in a Google Webmaster Help thread that Google may decide to "Skip URLs that repeat the same path element many times." So if you have a dynamic site and you use rewriting for your URLs but you do it in a way that shows the same path element too many times for many of your URLs, you may run into issues with Google indexing your site.

The site in question is wandelingen.nl. When you go to the site, immediately the URL changes to something like this wandelingen.nl/_/_/1/_/_/_/_/_/_/_/_/_ and as you click, more and more of those _/_/_/_/_/_/ elements get added on. Here is a GIF of the URL as I clicked only four times through the site:

So if you are rewriting URLs, don't do it in this fashion. John goes through a lot more with this webmaster to guide them in a way that makes this specific dynamic site more search engine friendly. It is a great technical SEO thread.

Consolidate duplicate URLs

If you have a single page that's accessible by multiple URLs, or different pages with similar content (for example, a page with both a mobile and a desktop version), Google sees these as duplicate versions of the same page. Google will choose one URL as the canonical version and crawl that, and all other URLs will be considered duplicate URLs and crawled less often.

If you don't explicitly tell Google which URL is canonical, Google will make the choice for you, or might consider them both of equal weight, which might lead to unwanted behavior, as explained in Reasons to choose a canonical URL.