Vaca DÃÂez is a province in the Beni Department, Bolivia. The two largest settlements in Vaca DÃÂez are GuayaramerÃÂn with a population of 35,764 in 2012, along with Riberalta with a population of 78,754. Vaca DÃÂez measures 16,228 km<sup>2</sup> (10,083 miles) in size.