Lisvane, Radyr, Cyncoed and Rhiwbina are the "rich areas" of Cardiff, might have some good stops there. Pontcanna too.
I doubt Rural Cardiff (Creigiau, Pentyrch, Tongwynlais et al) will have much in the way of Pokestops, but maybe I'm wrong.
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I doubt Rural Cardiff (Creigiau, Pentyrch, Tongwynlais et al) will have much in the way of Pokestops, but maybe I'm wrong.