Tsinghua of Peking University may limit the number of people. This is uncertain. You can try to arrive early. Remember to bring your ID card. Generally, you need to show it when you enter the door. Tsinghua suggested getting off at Yuanmingyuan Station on Line 4 and entering from the west gate, because the scenery of Tsinghua is generally concentrated here. Going east, you can see the lotus pond, the second gate, the auditorium, and the newly-built Tsinghua New School. There are souvenir shops along the way. If you go north, it's basically teaching buildings and student apartments. In Tsinghua, you can also consider taking a minibus directly at Ximen, 2 yuan each, and walking around the school. It is recommended to eat on the second floor of the lotus garden, open outside the school, and it is cheap. After returning to the West Gate of Tsinghua, take Line 4 to the East Gate Station of Peking University, directly enter the East Gate, and you will see the Peking University Library, and further north, Boya Building and Weiming Lake.