tyb
timemachine.eu is an effort in digitization 2d & 3d of european cultural heritage
archive.org has them geing back to 2018
https://web.archive.org/web/20180501000000*/timemachine.eu
Actual image they use on their webpage is
"Distinct Mind" by Unsplash (pic)
https://unsplash.com/photos/a-multicolored-image-of-a-multi-colored-background-Js9auX5_9R8