Where to announce your sitemap
- robots.txt: add the line
Sitemap: https://www.yoursite.com/sitemap.xml. All search engines will find it. Use the robots.txt generator. - Google Search Console: the Sitemaps section.
- Bing Webmaster Tools: the Sitemaps section. Bing shares data with other search engines too.
- Seznam Webmaster: worth it for Czech sites; Seznam then crawls the site more reliably.
Large sites
One sitemap may hold at most 50,000 URLs and 50 MB. Larger sites split it into several files joined by a sitemap index. This website does the same: a separate sitemap per language, one for the blog and one for images, linked from sitemap-index.xml.