Estrela do is one of the oldest breeds from Portugal. They are tough, large, athletic breed and make excellent watchdog as well as guard dog. They have worked as livestock guard dogs in the Serra da Estrela for over a century. Since the region was isolated, there was little breeding with non-native dogs, leading to the purity of the breed.
This breed is know workld wide now since American exported a couple of them to US in 1972, but untill then, it was unheard of outside of Portugal. They still work for sheperds and farmers here and also you come across many souvenir shops selling the puppies in the mountain. Puppy is so adorable but it grows so much that you make sure, before you fall in love with it, you have a big room for it to stretch its legs.
The dog in the picture might be a mixture of Estrela and Barnard but the CAT was so sweet trying to tack itself in the dog's fur. It is true that cats are not so good with cold temperature.