And for those parts of the world where flying a plane or trekking with a backpack is frowned upon, Google has called on an army of 40,000 people worldwide to contribute photographs and fill in details.
Sieberg calls them "citizen cartographers", and it's these foot soldiers who have built the maps of North Korea. (In the North Korean case, it was complicated by the fact that the cartographers couldn't get into the country itself: instead the maps were put together from the memories of people who had either visited the country or used to live there, and fact-checked against satellite imagery.)
When talking to Googlers about this, it's hard not to get swept up in the excitement. The "evangelism" of Sieberg and his colleagues is infectious.
But many people are worried about where it is taking us - not simply the Street View stuff, but the entire encroachment of technology on travel. The most widely expressed concern has been privacy: Nick Pickles, the director of the pressure group Big Brother Watch, has warned "you won't be able to sunbathe in your garden" without worrying about a Google plane spying on you in your bikini. (Sieberg is dismissive: "The resolution is not a concern for a person on the ground. It's just not going to be identifiable.")
And the internet giant has been forced to apologise after it was revealed that its Street View cars downloaded emails, text messages, photographs and documents from householders' wi-fi networks while photographing their roads.
These are serious issues, but some people are just as concerned about the risk Google Maps poses to the experience of travelling. Part of the joy is the mystery that surrounds a trip; not knowing what you will see or where the mood will take you. Maps can strip away that spontaneity.
"People spend a huge amount of time and energy and resources planning their trip, researching where they're going," says Aaron Quigley, a professor of human-computer interaction at the University of St Andrews.
"The risk is that you end up overplanning, when so much of travel is about serendipity, finding that little-known path."
There's also a risk that making it so easy to see anywhere in the world before you get there could take away the magic of seeing it for real for the first time. What's more, because Google Maps is linked to review sites such as Yelp or Google's own Zagat, there is the possibility that everyone will head for the same well-reviewed destinations.
"There's a risk that we all get sucked into this quagmire of sameness, a very banal, whitewashed sameness," says Quigley.
It's not all negative, of course. As Sieberg says, the other side of this coin is that new places become visible to us in ways they weren't before: "Whatever's around you, whatever's near you, opens up." It provides tourists with a way of avoiding the ghastly overpriced tourist traps around the main square, by showing the well-reviewed, reasonably priced ones a couple of streets away, and then allowing you to find them with Maps.
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