From space, the nighttime map of North Korea has a curious distinction: it is almost completely dark. Next door, South Korea glitters with great splotches of economic life, and, on the other side, China surges with energy. But North Korea has remained “an expanse of blackness nearly as large as England,” as Barbara Demick writes in “Nothing to Envy,” her profile of the country and its people. “It is baffling how a nation of twenty-three million people can appear as vacant as the oceans. North Korea is simply a blank.”

We got one step closer to filling in that void on Tuesday, when Google unveiled its first detailed map of what had been the last country on Earth to go unmapped by the digital Livingstones in Mountain View. The new map has subway stops in Pyongyang, a dictatorship’s worth of monuments and mausoleums, as well as hotels, hospitals, stores—and what are known to be facilities associated with several of the giant gulags.

Maps are so closely associated with power that dictatorships regard information on geography as a state secret. When I was a student in China in the nineties, the schools where I studied included “detailed maps” in the list of contraband, along with dissident memoirs and porn. Even recently, China has arrested foreign researchers who were seeking to acquire detailed data on the land, either for extractive industries or other purposes.

Looking at the new image of North Korea, I was, of course, appreciative of the meticulous work done by a group of volunteer “citizen cartographers,” who donated their data, Wiki-style, in a process that has also helped Google map other former blank spots, such as Burma.

And yet, the dominant sensation in seeing the spidery new detail on the land is that it reminds us just how much we still can not see. For now, it’s hard to envision how the map will have much impact inside North Korea, because almost nobody there has access to the Web. The delight we get in a digital glimpse of the North Koreans’ land only underscores the span between their reality and ours. The map allows us to indulge our curiosity, but we are just as in the dark as ever about the mysterious realm inside the heads of Kim Jong Un and his mercurial men. Politically, North Korea remains as black as a satellite map at night.

One major bright spot, however, is that in recent years we have come to know more about life on the ground, through a surge of remarkable writing and documentary projects. If the maps pique your interest, consider these three sources to learn more:

•“Escape from Camp 14: One Man’s Remarkable Odyssey from North Korea to Freedom in the West,” by Blaine Harden. The title says it all.

•“Nothing to Envy: Ordinary Lives in North Korea,” by Barbara Demick. The nonfiction account of everyday life.

•“A State of Mind.” The extraordinary documentary by British filmmaker Daniel Gordon about two female gymnasts, aged eleven and thirteen, preparing for the Mass Games.