Your XML sitemap belongs in your site's root directory at https://yoursite.com/sitemap.xml. This is the standard location search engines expect, and it's accessible to crawlers without additional configuration. If you're running WordPress with Yoast SEO or Rank Math, they generate this automatically at that URL. Shopify creates it at /sitemap.xml by default. For custom builds, you'll need to generate the file programmatically and place it via FTP or your hosting control panel. After placing the sitemap, submit it through Google Search Console under Sitemaps and Bing Webmaster Tools. This isn't technically required since you can reference it in your robots.txt file, but manual submission gives you index coverage reports and error notifications. Most sites should also add a sitemap reference line to robots.txt: "Sitemap: https://yoursite.com/sitemap.xml". This helps secondary crawlers find it. For larger sites in our portfolio (500+ pages), we split sitemaps by content type or section. WordPress handles this automatically with index sitemaps that reference multiple files like sitemap-posts.xml and sitemap-pages.xml. The main sitemap.xml becomes an index file. Google supports up to 50,000 URLs per sitemap file at 50MB uncompressed, but we keep individual files under 10,000 URLs for faster processing. Common mistakes: putting the sitemap in a subdirectory without proper cross-domain setup, forgetting to update it after site migrations, or including noindexed pages. At Ottawa SEO, we audit clients' sitemaps quarterly because CMS plugins sometimes break after updates and start listing 404s or redirect chains. Your sitemap should only contain canonical, indexable URLs that return 200 status codes. If you're seeing submitted URLs not indexed in Search Console, your sitemap likely contains pages Google doesn't consider valuable or crawlable.