Twenty-four tanks sit underground in a giant reinforced cave. When a winemaker enters the cave, they are greeted with the usual winey smells. But when they glance up, they see a curved dome of data displaying the status of each tank. If they’re at home and something needs to be adjusted, they can manage it via an iPad app.

In the 1990s, the Palmaz family bought Cedar Knoll Vineyard and Winery, which had opened in 1881 and then been abandoned during Prohibition. Renamed Palmaz Vineyards, the 610-acre parcel lies on the southern edge of Napa Valley. Because it includes the forested ridges of Mount George, the family could dig 18 stories into the hill.

A computer drawing of Palmaz’s underground facility shows the intricate tunneling system that spans roughly three city blocks. This layout allows the winemaker to use a gravity-flow process—the vino flows from one step to another without aid of mechanical pumps, meaning it’s agitated as little as possible. (Many winemakers believe that the fragile tannins do better when they’re not jostled around.)

During the key summer growing months, the winery sends a small Cessna up to capture infrared images of the vineyard canopy. (The amount of light reflecting off its surface translates to the amount of chlorophyll in the leaves.) Software then compares the plants’ vigor to the amount of moisture in the soil, so staff can analyze each parcel and decide exactly where and how much to irrigate.

More than 100,000 tons of rock were excavated to create the massive cave, and the stonework on the facade of the main entrance at level 4 is mostly composed of a crystal-like rock called rhyolite that was extracted from the mountain during the dig. The work began in 2000 and took seven years to complete.

After the grapes are harvested, they’re destemmed. Then they move along a sorting table—the balcony at the top left of this rendering. They drop from there into one of 24 fermentation tanks that spin atop a giant carousel. Each parcel of land gets its own tank. The outer ring, yet another level down, holds French-oak barrels where the wine will age for two years.

A Fermentation Intelligence Logic Control System screenshot. The map at the top left shows which parcel of grapes is being held in this particular tank. At the top right is information on the glycol supply. (Glycol is the liquid that flows into four steel jackets, wrapped around each tank, that enable the team to heat and cool the huge containers.) Vibrating probes within the tank tell the winemakers what the density (and thus the sugar content) of the juice is. That’s displayed as the blue line in the graph at bottom.

A so-called sensory-neutral tasting salon in the Palmaz cave where staff conduct wine and food pairings. The rooms include interactive digital walls that display blend maps and tasting notes. The data from the vintages can be displayed side by side for comparison purposes.