What is the best way to implement a branch in another city on the site?

Question

Joomla

The site was originally dedicated to the Moscow network (information about branches, contact details, directions, list of services, etc.), in the near future there will be an expansion to St. Petersburg, it is necessary to make a "branch" on the site, for those who are from St. Petersburg .
How it is better to implement it? Create a subdomain and switch at the top Moscow / St. Petersburg? Or maybe site.com/spb?
Thanks in advance for your replies.
Add. inf.:
Geolocation detection is unlikely to be connected (the old joomla site is based on snot, plans to redo it, but we will redo it later than we need to launch a branch).

Answer 1

A subdomain is better than a subdomain. Perceived by search engines as a separate site. It is advisable not to duplicate the main content.