In canon, it seems to be visible. to Muggles. The scene where Voldemort kills the Riddle House caretaker seems to imply that (although not fully since it turns out we are getting the scene from Harry’s mental connection to Voldemort).
In canon, it seems to be visible. to Muggles. The scene where Voldemort kills the Riddle House caretaker seems to imply that (although not fully since it turns out we are getting the scene from Harry’s mental connection to Voldemort).