Foot treading, stomping grapes by foot to extract the juice, is at the heart of the making of authentic port wine. It is a very traditional and labor-intensive method, yet it is still the one producing the finest ports. We visited Quinta de Vargellas, a wine estate owner by Taylor's, one of the founding port houses. Although port wine bears the name of the seaport city of Porto, it is actually in the steep hillsides of the Douro Valley in northern Portugal that it has been made for centuries. The region was legally demarcated by the Portuguese government in 1756, meaning that authentic port can only be made here.