Siheyuan is a common quadrangle building in the north. ()

Courtyard is an outdoor open space and a place for outdoor activities, and patio is an integral part of indoor space. As a transitional space between the hall and the main hall, it is integrated with the whole building and has no specific interface, but it has many uses. Courtyard can be large or small, with irregular land use and flexible layout. The patio is constrained by the main building (house), which is based on a rectangular single paddle with an aspect ratio close to 5: 1. There are patios in traditional houses all over China, especially in the hot and rainy south, from quadrangles in the south of the Yangtze River to Hakka earth buildings, from diaojiao buildings in Miao and Dong areas to the "four-in-five patios" in Yunnan Plateau, and even watchtowers and arcades in Guangdong, the products of modern integration of Chinese and Western.

The most representative patios in Huizhou architecture are "high-wall small well" and "full-hall well", and there are small and exquisite patios everywhere, which are completely out of proportion to the tall horse-head wall. There are many giants in Huizhou history, even the mansions of large families are small patios, with a small area and a large number, and even a spectacle of "36 wells" or even "72 wells" appears.