We visited some when school was in session and some when it wasn’t. If you’re visiting several schools in one trip it’s difficult to avoid since they all have different fall breaks and spring breaks etc. For example, Bates was on fall break while Colby was in session, one day apart. The school my S chose (Tulane) we visited in summer because it came on his radar later in junior year. So he saw it in the heat and without students and still chose it. We’re heading to admitted students day this spring so he can see a bit more and know what to expect (and reduce any August anxiety), but he is already committed. This second trip is not “necessary” but since we don’t have to visit any other schools this spring, we’re doing it. If he had not gotten in to Tulane we would have had a couple of yet unseen schools to consider in different states.