Foreign tourists watch the sunshade and fish tank in a Siheyuan. (Photo/people.cn)

Foreign tourists take a pedicab in a Hutong. (Photo/people.cn)

The exterior of a Siheyuan. (Photo/people.cn)

A corner of a Siheyuan. (Photo/people.cn)

A foreign couple spends days in a Siheyuan guesthouse. (Photo/people.cn)

A teacher teaches foreign tourists to play Guzheng (a traditional Chinese instrument) in a Siheyuan guesthouse. (Photo provided by Zitan Siheyuan Guesthouse)

The courtyard of a Siheyuan. (Photo provided by Zitan Siheyuan Guesthouse)

Siheyuan, the traditional Chinese quadrangle courtyard, is one of Beijing's most important cultural cornerstones. How many Siheyuan does Beijing have? According to the "Qianlong Beijing Map" made during the reign of Qing emperor Qianlong (1736-1795), there were a total of 26,000 Siheyuan in Beijing at that time. Statistics from the Beijing Research Institute of Ancient Architecture show that Beijing had over 6,000 Siheyuan in the 1980s, and about 3,000 of them were well preserved.

However, as parts of the old city were remodeled over the last 50 years, over 80 percent of Siheyuan have disappeared. Nevertheless, when tourists come to Beijing, Siheyuan are always a "must see." More and more foreigners are falling in love with the disappearing Siheyuan, and some even come for the exclusive purpose of seeing Siheyuan with their own eyes.