Recently we had a very informative seminar from a UT student Sandra Benyamin. There were some unusual sites she recommended. As we slow down our travels and have mobility issues we can still see the world.
My favorite is a site called Google Cultural Institute. It is composed of several different modules, like the Art Project, Users Galleries, and World History,
Here is a snapshot of the home page. when you click on the Art Project module, you have the ability to search by gallery, location or artist. As an example I searched for John William Turner. Within seconds they found all the Turners on display in a variety of countries.
You can filter by place,and collection.