Mine ended at 2:30, but it could be as late as 4:30. Everyone goes on the tour, lunch, and curriculum presentation. Then at 12 you will have your student interview. Then your faculty interview could be anywhere from 1 to 3, but I think most people had them at 1. After that there is a small 5 minute interview with someone on the adcom (the only open file one) just to see how your day went.
Mine ended around 4:00-4:30pm. It depends on when your afternoon interviews are scheduled, and how long they take (I got into a long conversation with my last interviewer).
