Without creating subdomains or how, but there is an alternative.
Examples of sites with subdomains:
In the second case we are dealing with well-known brands. The approach to online promotion is somewhat different.
In most cases, you need to create a subdomain and be sure to register each domain as a separate website in webmaster and assign each the appropriate region (this applies to Yandex, with Google a little differently). It is necessary to say that the approach to promotion will differ depending on the region. This is quite a laborious process. You need to consider many factors in ranking.
PS. When I worked in the Studio of Internet marketing (quite famous in Russia) were projects that included the promotion of 15 to 20 regions and every SEO-specialist engaged in the region. So based on my experience and the experience of the Studio will say that it is advisable to create subdomains.