When John Curlander and his team at Microsoft's Virtual Earth first began to build their first 3-D online city about a year and a half ago the job seemed daunting.
"The traditional way to build out a city is essentially one building at a time," he told me.
"At the time we evaluated how long it would take and it would have been hundreds of years in the making to do a single city. Today we still call this 'Project Pyramid' for that reason."
But tonight, Microsoft's Virtual Earth 3-D goes online with three-dimensional images of 15 major American cities. Through its Live.com website, you can swoop down the Las Vegas strip and fly in between the casinos. You can soar over the St. Louis arch or around Seattle's Space Needle.
"What we've developed, Curlander says, "is an automated way to go from the original photographs to the finished 3-D model."
And with that step, Microsoft may have lifted internet mapping to a new level. Many of us have used Google Earth to zoom through the atmosphere down onto our street to see what our house looks like from above. But in those images the world is flat. Virtual Earth 3-D will give you an entirely new perspective.
Microsoft is spending hundreds of millions of dollars to develop Virtual Earth and ultimately the company wants to take their 3-D maps right down to the street level. Vans equipped with multiple cameras are now driving cities all over the country firing off images in every direction. Curlander says it takes a couple of weeks to drive a city and collect the 6 million ground level images needed to map it.
The goal, he says, is to provide a real world experience. It's still years away, but in the near future, sitting at your computer at home you'll be able to walk down a street anywhere in the world, "walk inside a store, go shopping, pick up the merchandise, evaluate prices."
"Ultimately," Curlander says, a smile curling on the edge of his lips, "the goal is for this thing to become alive."