How do you impress a king? Here's one idea—give him a giant book.

That's what the Dutch sugar merchant Johannes Klencke did in 1660, when English King Charles II was restored to the throne (and he became a baronet as a result). The atlas, which stands approximately eight feet tall and contains 41 wall maps, was one of Charles's most prized possessions, symbolizing his dominion over all the world's knowledge. The atlas remained in the royal family for 150 years. It became the property of the English people after the death of George III in 1828. Now it's accessible to anyone who wants to have a look at it.

[Image: British Library]

"It's so big, it's so over the top, it's so impractical, it's like some monumental baroque curiosity, and that was precisely its value to the king," says Tom Harper, the lead curator of the British Library's collection of about 50,000 antiquarian maps at the British Library. The Klencke Atlas contains maps of the British Isles, the Netherlands, Italy, France, as well as maps of China, the Middle East, the East Indies, and classical maps of Europe and Greece.

[Image: British Library]

Now in the possession of the British Library, the Klencke Atlas has been photographed in its entirety and is available online for anyone to peruse and study for free.

"For all that time, it's been in theory available for anyone to come and look at because it's a public possession," Harper says. "But in practical terms that's impossible because it's such a complicated object to look at."

Harper says that if you did want to look at the atlas itself, it would require four people to hold the edges, and another two to hold the giant pages flat. In order to photograph it, the library had to acquire a new large-format Sinar camera, valued at approximately $51,000–but it wasn't high-resolution enough on its own. Each digital image is a composite of eight photographs, and has a raw file size of 1.16 GB. Because the 400-year-old paper doesn't lie perfectly flat, making it difficult to photograph, the team of image technicians had to photograph it at different heights and blend the images together to create the illusion digitally that the paper is flat and undistorted. The photography and postproduction process took a month to complete.

Because the atlas was so difficult to peruse, many of the maps have never been studied sufficiently, Harper says–though since the book was only recently been put online, they haven't learned anything new just yet. While all of the 41 maps are prints made from engravings, five of them are the only prints that survived to the present day, and most of the rest of the maps can only be found in all three of the world's three giant atlases–the one owned by the British Library, one at Rostock University that was originally presented to the Duke of Mecklenburg, and a third at the National Library in Berlin, which was given to the Great Elector, the Duke of Prussia.

"The maps are regarded as the masterpieces of Dutch cartography," Harper says. "Dutch mapmakers are regarded as producers of the finest historical maps ever to have been produced."

[Image: British Library]

Some of the maps are the results of the first scientific surveys of places in Europe. One map of the Ukraine produced in 1648 was the first known map to be printed to assist in a military campaign. It was created by a French mapmaker working for a Polish king who measured the distances between towns by strapping an odometer to his horse, phased to his horse's gallop–almost like a 17th-century Fitbit.

The digitization of the Klencke Atlas is part of a larger project to digitize 50,000 of the collection's most precious antiquarian maps, which include the very first map of New York City, maps from the Revolutionary War, and maps by the 18th-century British explorer Captain James Cook. Harper hopes the digitization will be completed by the end of 2017.

While the Klencke Atlas is no longer quite so impressive in its digital form, its new home on the internet is a fitting legacy for a book that was meant to symbolically contain all the world's knowledge.