Paseo del Morro is the path that runs outside the San Juan city wall. I walked this path yesterday, and at the start noticed the sign above. Further down the path, this is an example of what I saw:
They were big and small and friendly and mean and active and lazy. Fed by the council, dozens and dozens (hundreds?) of wild cats live outside the wall on the ocean’s edge. As far as a feral cat community goes, they seemed contended enough with their lot. As far as an unexpected attraction for this tourist is concerned, this rated a thumbs up 🙂