First, I thought this was a viewpoint because of the map symbol so I searched in vain to find the activation point but couldn't find it so I decided "this is a nice-looking place so I'm going to take a screenshot of it" Then I got a notification that said something like "Captured a photo trophy". So, I checked the photo manager in game and found the page that showed all viewpoints and photo trophies in game. That update to photo manager must have come with ATS 1.46.