There’s a lot of art out in the world and much of it is hidden in closed collections just because there isn’t enough room to display it all. The British Library wants to share its archives with the world and has uploaded a ton of art that you can view (and use) for free.
The collection includes portraits, adverts, maps and all manner of other illustrations, paintings, and drawings that the curious can browse through and explore times gone past. Because this is a library it also has book covers and children’s book illustrations which is something that many other online archives lack.
The images were put online by the Mechanical Curator, a bot that just posts them, while they were organized by human volunteers. There are literally thousands of images to browse through and enjoy. They’re all copyright free so feel free to do whatever with them. Use them in new work, as inspiration or in their full glory. Check out the website to waste some time.