Is Google still including sitelinks to your previous event’s website in the search results? Google generates these links automatically, based on the traffic patterns for your domain. To let Google know that some links are redundant, your best option is to use the Google Search Console (formerly known as Google Webmaster) to ‘demote’ these links. Per Google, “demoting a URL for a sitelink tells Google that you don’t consider this URL a good sitelink candidate for a specific page on your site”.
Only site owners and users with full permissions can demote sitelinks. Here is a step by step guide on how to submit links to Google for demoting:
On the Search Console Home page, click the site you want.
Under Search Appearance, click Sitelinks.
In the ‘For this search result’ box, complete the URL for which you don’t want a specific sitelink URL to appear.
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