Hi Lizkitt
I apologise that no-one in the Marbella area has responded to your question yet.
Maybe they are all out walking their dogs!
Seriously though, we own in Costa Blanca, so can't comment on the Costa Del Sol area.
However, there are plenty of "Parc Naturelle" (I think that's how it's spelt), in Spain.
This would be the place to take your dog for long walks.
Be English though and take a pooper scooper and bag with you!
The Spanish don't and it's not very nice to come across doggy doo doo's in these beautiful natural areas within Spain!
Kind regards,