Note: This calendar view maps the number of captures of http://www.unesco.org/new/en/communication-and-information/memory-of-the-world/register/full-list-of-registered-heritage/registered-heritage-page-1/the-archives-of-negatives-publications-and-documents-of-manuel-alvarez-bravo, not how many times the site was actually updated.
Look Up URL in general Internet Archive web collection.