Whether you are just wine curious or a wine collector, Master Wine Tours has a tour for you. Napa Valley is only about 30 miles long, six townships. It is considered an appellation (AVA) with 16 sub-appellations and some 500+ wineries. So creating the perfect Napa Valley wine tour may require some planning. To lay out a great tour, it takes a little know how. So if you are not quite sure where to start, we will assist you with the where, what and how. Cheers.