Amtrak from Los Angeles to the Central Coast Wine Country
If your hopes are set on an overnight wine tour, the best idea is to hop on an Amtrak Rail at Union Station in Los Angles and head up to Santa Barbara. From there, there are a several companies that offer wine tours of the southern-central coasts wineries. After a day of wine tasting, stay in Los Olivos or Solvang, then hop another train the next morning and head to the central coast wineries in Paso Robles. Paso Robles is home to some of the world's most popular new wines, such as Justin Vineyards, and is gaining popularity for its rustic charm.
The Train from San Francisco to Napa Valley Wine Country
Just as there is no magical express to takes you from the south-central coast, through the central coast, the same is true for the northern wineries in Sonoma and Napa valley. However, again it is possible to travel via train. Amtrak runs up and down the California coast, and there are wine tours available to pick you up at the station, such as Wine and Dine tours. From the station, you can meet with a wine tour guide to show you the wineries of your choice.
Napa Valley Wine Train
If you must have a wine tasting on a train, then the Napa Valley Wine Train is a solid choice. Although the train doesn't run overnight, there are overnight packages which provide a ride on the wine train, local winery tours and stays at local hotels. However, the train ride itself is a three-hour tour of the scenic valley from historical Napa to the beautiful St. Helena.