Do multiple sitemaps damage your site indexing?

• I just took on a very large e-commerce site and they have tens of thousands of URLs that need to be submitted and monitored in Google. I was planning to break these up into multiple sitemaps but wasn't sure of the risks/benefits? Can you provide some recommendations?

Answer: This is a very common strategy and we don't anticipate any problems with what you have described.

In fact, Google encourages site owners to set up and submit multiple sitemaps depending on whatever way is easiest for them to maintain these specific parts of their site content.

For instance, let's assume your site offers a blog, a forum, and several products. Each could have its own XML sitemap. Maybe you set up a couple of subdomains on your site or have a large video tutorial inventory. Each subdomain may need a unique sitemap to ensure proper indexing or you could set up a video sitemap to organize and index that content specifically. Your decision depends on how much control you want to present to Google when they visit these uniquely organized sections of your site.

Most large content or product-rich Web sites submit multiple sitemaps into their Google Webmasters Account, categorized by business, product or service. The appropriate way to do this and organize it as effectively as possible is through a Sitemap Index File. In a nutshell, it's a sitemap that lists other sitemaps. Here's an example, in XML format, listing two sitemaps:

It's important to know that a sitemap index file can only specify sitemaps that are found on the same site as the sitemap index file....