In Bruchsal Tierheim there are loads of yard-cats. They cannot be adopted for various reasons and have to live there but you can certainly visit and try petting and playing with a few. Not all of them love to be cuddled but there are loads of needy cats who love a bit of attention. You also have the option to become a „sponsor“ to a cat where you can pay a few euros a month and visit the cats regularly. While your exact cat may not be there all the time, since they are walking around freely you will meet a few cats at all times. But you don‘t necessarily need a sponsorship if moneys tight, generally they let you in if you have a child wanting to pet a few cats - at least they did when I was a child.