Dogs, documentary, South America, bbc?

[Barchettaman]

Evening people,

I have a memory of a documentary about dogs in S America who where let out city-wide in the morning, who all went up to some hill/park, and then returned in the evening.,,?

Any ideas what I may have seen?

[KAgantua]

it was this

https://www.youtube.com/watch?v=Qkuu0Lwb5EM