If you use GSC it can show you the terms and position of the page in question, though it is kind of indirect searching because they show the 'term' searched and your URL's position for that term, but it can be more than one term so not very useful. If the main 'term' shown can be related to other topics, then you might see a pattern.

Thanks, as much as I have tried to avoid G products I may have to succumb to GSC to see what it analyses from a couple of my sites.

For this specific page to be easily beating all others apart from the index is perplexing to say the very least, then again I had one visitor the other day actually download a 5mb pdf 180 times, yep 900mb, bizarre!

A sudden spike like that can come from quite a few places, even if rankings haven’t visibly changed.

My checklist would be:

- Compare the top search queries before vs after the spike. Often it’s demand that’s changed rather than rankings.
- Check impressions as well as clicks. A broader query match or seasonal trend can expose the page to a much larger audience.
- Review referrers and user agents for signs of bots, AI crawlers or scraper traffic skewing your analytics.
- Check server logs for unusual IP ranges, countries or repeat requests.
- Look for temporary backlinks or mentions. I’ve seen bursts of inbound spam links coincide with a short-lived visibility boost before disappearing again. Correlation isn’t proof of causation, but it’s something I’d investigate.
- Search for recent social mentions, newsletters, forums or AI citations that may have surfaced the page.
- Compare against Google update timelines. Sometimes a single page is temporarily re-evaluated even when the rest of the site looks unchanged.
- Check whether the page has started appearing for new long-tail queries rather than simply moving up for existing ones.

If nothing obvious turns up, I’d lean towards one of three explanations: increased search demand, Google testing the page across a wider query set, or an external mention/referral that isn’t immediately obvious. If it proves to be genuine user traffic rather than bots, I’d be looking closely at what Google has changed about that page’s query profile rather than focusing only on the headline ranking.

Look for temporary backlinks or mentions

We've been discussing about this over coffees and this has been my conclusion too since all of your other welcomed suggestions have been gone through. Let me say that it's causing us no issues, simply intrigue.