Guyaju is a historic site of more than one thousand years history. It lies to the northwest of Yanqing County, the suburb of Beijing.

The caves were made on a precipitous cliff by a group of ancient people who were not accounted in any history book. There are 117 caves in all. The artificial stone rooms were arranged one by one on the steep cliff in the gorge. They are rectangle or square in shape. The biggest one is about 20 meters in length and the smallest one is only 3 to 4-metre-long. Some caves are made up of one room and the others are made up of several rooms. They are parallel and designed to be two stories cave. Among them there is a big two-stories cave flanked by small rooms and columns. It may be a place for material or sacrifice and to be called 'Guan Tangzi'. Some one thought it was constructed in Yuan dynasty and others supposed it was the home of gangsters or the camp of army, which escaped from war. Today, it is still a riddle to people.