change category to sub category- keep URL?

VERSION: ZENCART 1.3.7

We have inherited too many product categories, and I need to re-organize them into main categories and subcategories, for easier viewing by customers.

But worried that if I move the product to a sub-category, the URL will change and lose the link to that posted on other people's websites...

Is this true that this would happen?

Is there a way around this problem?
Because we can't keep having 35 main product categories!

I've checked google and forums and not found anything specifically this problem-- I know how to move categories and create sub-categories, just not how to lose the link.

maybe a difference between main category and parent category?
maybe keep the categories the same but just change how they appear to customers on the sidebar?

thanks to anyone for your help!

You could use 301 redirects from the old categories to your new subcategories. That would automatically shift visitors to the correct new locations, and search engines would pick up the 301 (="moved permanently") and adjust their search results over time.

By the way, if you are still on v1.3.7, you need to upgrade to keep your site from being hacked.

Wow thanks!

didnt know needed to upgrade, and this sounds like an EXCELLENT solution for the subcategories. I am a novice and didnt know about 301s--my boss will be thrilled.
many thanks!