National Geographic has been producing thematic maps for decades, revealing not just physical features but also location-based details on cultures, history, wildlife, science, and more. Now, a treasure trove of more than 500 of those maps are available online in a new service from Google Maps.

The National Geographic maps can be found in their own section of Google Maps Gallery, which launched officially on February 27. This includes reference maps, wall maps, National Geographic magazine supplement maps, and other creations from over the years, all laid on top of the relevant Google basemaps.

"It's pretty epic to have all this stuff up online," says Frank Biasi, director of digital development for National Geographic Maps in Evergreen, Colorado.

Biasi says the new tool takes advantage of the Google Maps Engine on the backend.

"That's for organizations to publish maps for their own websites primarily, but Google Maps also has a public data program and they have invited certain publishers, including the Library of Congress, the World Bank, and National Geographic, to share maps publically through Google's Map Gallery," says Biasi.

"It's part of Google's mission to organize the world's information and make it universally accessible and useful."

The new maps galleries are being integrated into Google search results. Biasi says, "If someone does a search on 'India map' or something like that, any of our maps that have those words may come up in the list of results."

Biasi says he hopes the maps will be useful in educational settings and for "anyone who is curious about the world and how it used to be." He pointed to a thematic map of medieval England that was made in 1979 as a favorite.

"These maps contain a lot of carefully researched knowledge in addition to cartography and geographic features," says Biasi. "They can show how boundaries change, the distribution of people and languages, and many environmental issues."

Biasi adds that the maps can be embedded into other web pages or apps, and that Google may add an e-commerce element so that people can pay to download high-resolution versions of the maps. Each map already has a link to buy a print version.

"National Geographic members have always loved our maps, whether folded in our monthly magazine or purchased in stores or online," says Biasi. "The Maps Gallery puts our map collection at their fingertips."

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