(Wired) - I’VE BEEN SPENDING some time in wine country recently, renting a cabin from friends. Every morning I sit out on the deck, drinking coffee, reading, and admiring the view, which you can see in a photo below. In the time I’ve been here, the vineyard across the way has turned from sparse and brown to bushy green, and that got me wondering: Whose vineyard is it? What kind of grapes are they growing? Is the wine any good?

In trying to figure that out, I eventually stumbled on a map-driven website for wine industry insiders. It was developed by Jordan Thomas, a cartographer who grew up here in Sonoma county. Jordan was quick to tell me that the point of his site isn’t to satisfy the idle curiosity of wine country visitors like me–it’s used mainly to help match vineyards that have grapes to sell with winemakers who might be interested in buying them. That said, it’s a also a great way to satisfy the idle curiosity of wine country visitors like me.

My first attempts to figure out what grapes I was looking at were pretty crude. I looked up the area on Google maps. The cabin is on Fitch Mountain in Healdsburg. The Russian River follows an S-shaped course here (you can see it below in the 1898 map from David Rumsey’s collection). The cabin is roughly in the location of the big W, and the view is to the north. Picture two eyeballs nestled in the arms of the W and you get the idea. The bottom half of the S is the river winding its way around Fitch Mountain. The top half, according to Google, is called Digger Bend. That’s where the vineyards are.

You can see the vineyards in Google’s satellite imagery, but there’s no identifying information. Googling the likes of “Digger Bend vineyard” got me nowhere.

My breakthrough came when I found Jordan’s site,Everyvine. But I didn’t find it on Google. I’d noticed a surveyor’s office near one of my favorite brunch places in Healdsburg and stopped in one day. It turned out to be the firm of Brad Thomas, Jordan’s father, who showed me around the office, patiently answering my questions about surveying and aerial mapping, and obliging my request to look at some of his maps. When I told him about my grape quest, he told me about Everyvine and suggested I call his son.

Jordan lives in southern California now, but he got interested in maps working at a map store his dad owned for a while in Windsor, a small town here in Sonoma county. Wineries would occasionally ask the Thomases if they could make decorative maps of their property, the sort of maps you see hanging on the wall in tasting rooms. So, Jordan studied graphic design and started making winery maps.

But that piqued his interest in another question: “For a particular wine that I like, can I know where the grapes came from, other than the verbiage that the winery’s marketing team came up with?” Not really, it turned out. A lot of that information is private, and no one had ever tried to make it accessible.

Jordan created Everyvine as a crowd-sourced mapping site for the wine industry. Vineyard owners or managers can enter basic information about their property, such as which grape varietals grow on different blocks of land, which clones and root stock they’re using, when they were planted, how the vines are spaced and trellised, and so on. It’s all voluntary, and participation varies. Coverage is best in Sonoma County, where Jordan estimates Everyvine includes entries for 80 percent of vineyards.