Use this visual search engine to find public domain images from Museums all over the world.
Museo is a tool that searches public domain images from multiple museum’s collections at the same time.
This visual search engine searches the Art Institute of Chicago, the Rijksmuseum, the Harvard Art Museums, the Minneapolis Institute of Art and the New York Public Library Digital Collection (with more to come).
Every image you find here is in the public domain and completely free to use, although crediting the source institution is recommended.
These aren’t the usual free images found in stock and clip art sites, these are usually unique and unusual. Some images showed up multiple times in the results, and some weren’t particularly related to the search term – sheet music seemed to appear in most search results I tried, but all in all an interesting variety if you want something you won’t find in stock photo and clip art sites.
(the article image shows the results of using the search term “mountains”)