In "The Silverado Squatters," Robert Louis Stevenson describes Schramsberg's founder Jacob Schram's "serious gusto" to produce incredible vintages that America and indeed the world had yet to taste. More than 150 years later, Schram's winery is still producing delectable wines, according to recent visitors. Tours led by friendly guides detail the property's history, the beautiful rows of vines and particularly, the winery caverns. Carved in the 19th-century, these caverns hold approximately 2.5 million bottles of precious wine. 

Recent visitors said the winery tour is interesting — especially the historic caves — and worth the extra money. But many advise travelers to book their tour far in advance, as there are a limited number of spots and they tend to fill up fast. And, of course, many rave about the sparkling wine, the vineyard's specialty.  

Located in Calistoga, California, Schramsberg Vineyards offers six tours daily between 9:30 a.m. and 2:30 p.m. The tour, which usually takes about an hour and 15 minutes costs $60 per adult (visitors younger than 21 and pets are not allowed). For more information, check out the vineyard's website. If you'd like to visit more than one more winery, consider signing up for one of the best Napa Valley tours.