The Rijksmuseum offers a vast collection of high-resolution artworks that are free to use. Their Rijksstudio platform allows you to download and incorporate pieces from their extensive archive of Dutch masterpieces, making it a valuable resource for historical and artistic elements in your collages.
The Met offers access to over 500,000 images from their collection under the Creative Commons Zero (CC0) license. This includes paintings, sculptures, prints, and other artworks.
The NGA offers free access to high-resolution images of artworks from their collection through their NGA Images platform.
The Cleveland Museum of Art is proud to be an open access institution, offering the public the ability to download, share, collaborate, remix, and reuse images of public-domain artworks from the museum’s collection, as well as metadata for the entire collection—all without asking permission. High-resolution images (tiff) and data related to the CMA’s collection are made available under a Creative Commons Zero (opens in a new tab) (CC0) designation.
Unsplash’s Archival section is a treasure trove of high-quality, free-to-use images with a focus on archival photography. These images are perfect for adding a vintage or historical feel to your collages. Remember that while Unsplash offers these images under a very permissive license, it’s always good practice to double-check each image's details.