What is the best way to implement site regionalization?

Question

Search Engine Optimization

there was an old ugly domain, let it be OLD.ru (Vologda region)
a year ago I made 301 redirects to a new domain, let it be NEW.ru (changed the region of the new site to Moscow in connection with moving there)
Now I want to make a site for each region: Peter , Kazan and restore the Vologda region.
What if we just remove the 301 redirect from the old OLD.ru domain? won't it affect the fact that he transferred his weight to the new domain for a long time?
which is more correct?
Option 1:
OLD.ru (Vologda) <---- if you just remove 301. What will happen to the positions if the site has been a 301 redirect to NEW.ru for more than a year?
NEW.ru (Main domain. Moscow region)
spb.NEW.ru (St. Petersburg)
kz.NEW.ru (Kazan)
Option 2 ?
OLD.ru (old domain, Vologda)<---do not touch, do not remove 301
NEW.ru (Main domain. Moscow region)
spb.NEW.ru (Peter)
kz.NEWru (Kazan)
vol.NEW.ru (Vologda ) ) <--- if Vologda becomes a subdomain ?
or how else?) Something I'm completely confused with these regions of Yandex)

Answer 1

Just answered a similar question. I will copy.
We do it for large projects, where there are many cities - after all, it is the subdomains that are different (gorod.site.ru). Because to promote the project throughout Russia is a long and expensive pleasure, because the regional issuance is even higher. For a subdomain in Ya.VM, a region is set and the site becomes a regional one. And it is easier to promote kemerovo.potolki.ru in Kemerovo than potolki.ru throughout the country, on request "stretch ceilings". Content - yes, it should be different. But often enough difference only in the city. Those. scripts themselves sign "stretch ceilings in {city}" and titles, descriptions, texts, h1.
In your specific case, I would do this:
OLD.ru (old domain, Vologda) - 301 on vol.new.ru
NEW.ru (Main domain, Moscow region)
spb.NEW.ru (Petersburg)
kz.NEWru (Kazan)
vol.NEW.ru (Vologda)
only, even so, I would write the cities in full, without abbreviations.
In some cases, we have a bunch of troubles causing the correct distribution of content across subdomains. For example, robots have a lot of rules so that information pages (about the company, help, advertising, investors) and all sorts of articles (useful articles, blog, news (if they are about the project, without reference to cities)) - we put them on the main domain and prohibit to indexing on subdomains. Sold content, respectively, vice versa.

Answer 2

I would not make cities the 3rd level of the NEW.ru domain. It is
better to make a subfolder from the old domain - make 301 redirects.
Further - by subjects (districts, regions, etc.): here is a list
And here : country, county, and city codes.
And we combine: site/country-region/city/ ,
making a 301 redirect for Vologda (for others - similarly) to this folder from the old one (also do not forget to indicate the new URL in the sitemap: sitemap.xml, if the URL has been changed):
Do not confuse regions/states of the country with language codes !
Also, I recommend reading more about geotargeting in Google Help (in Russian): here
Here is what is important for targeting by city:

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Google не использует для геотаргетинга ни метатеги расположения (например, geo.position или distribution), ни атрибуты HTML.

Answer 3

kz ассоциируется так то с Казахстаном.
vol похоже больше на volume
лучше поставить тогда
kazan.new.ru
vologda.new.ru
так будет более понятно.