Cities Around the World is a site from the American Geographical Society that has thousands of photographs from…….. cities arounds the world. You find the link to this site on my Geography page under the Sites That Cover Many Areas section.
You can also save photos to a “Favorites” section, though they won’t actually “host” your collection. They make it easy, though, for you to save it on your own computer.
Students can also easily use the photos in one of the many online applications available on my Examples of Student Work page. These include the ones listed under Student Slide Shows and Student Flip Books. The website is pretty explicit in giving permission to students and teachers to use the photos in this way.