What is the Alabama of your country?

Hi everybody, my girlfriend showed me a Tiktok about manga authors adding unnecessary incest plotlines to their works and I thought immediately "They are from Monterrey" (we are from Mexico).

I remembered that the States have a similar joke about Alabama and I started wondering if other countries also have a state or city associated with people who are, for some unknown reason, attrated to their cousins.

Here in Mexico there even is a kind of saying for these people «A la prima se le arrima».