在清朝康熙年间，乾清门就是举行御门听政的地方，而在西侧还有一排连房，就是军机处，他是在雍正年间设立的，直到辛亥革命爆发的时候才被废除。军机处是一个非常重要的机构，凌驾于内阁之上，但是当时为了防止泄密事件的发生，督察院每天都要派御史到军机处旁边的内务府值班，监视这里的活动。
现在大家看到的就是乾清宫了。乾清二字取自唐代韩愈《六合圣德诗》中的诗句：“乾清坤夷”，意思就是天下清和，各地平安。在明朝和清朝初年，皇帝的寝宫一直都是这里，到了雍正皇帝以后，就挪到了养心殿，从此，乾清宫九成了皇帝听政的地方。在每年过节的时候，皇帝都要在乾清宫举行庆典活动，清朝康熙乾隆年间，还在宫内举行了“千叟宴”。而且“康熙智擒鳌拜”的故事也发生在这里。而且皇帝死后，必须要在这里停灵，祭奠15日，表示寿终正寝，之后才可以转移到其他地方。在乾清宫内正中设有金漆宝座，后面还有屏风，上面刻有先帝的圣训。在宝座上方还高悬着“正大光明”的匾额。在雍正皇帝即位以后，对于争夺皇位的种种弊病，他发布了秘密立储的上谕，从而改变了封建王朝公开册礼太子的制度。此后，皇帝亲自写储君谕旨两份，一份儿放在这块正大光明的匾额后边，另一份儿则自己藏起来。在皇帝去世以后，拿出两份诏书核对无误以后，即可生效。
在明朝，围绕着乾清宫还发生了三大疑案。就是壬寅宫变，红丸案还有移宫案。壬寅宫变就是在明朝嘉靖年间，皇帝正在乾清宫中睡觉，宫女杨金英等16人一起下手，想把皇帝杀死，但是在慌忙之中却把绳子打成了死结，所以没有成功。结果这些人就全都被处死了，这年正好是壬寅年，所以称为壬寅宫变。自此以后，皇帝不敢在乾清宫中居住，直到临终前一天才回到了这里，但是当天就死了。红丸案的发生是在明朝万历皇帝朱翊君死了以后，他的儿子朱常洛即位。但是不久他就病了，服用了进贡上来的红丸，吃了一颗感觉很不错，所以有吃了第二颗，结果就死在了乾清宫内，前后只作了29天的皇帝，所以被人们称为一月天子。移宫案是在一月天子朱常洛死了以后，他的爱妃李妃有野心相当皇后，所以就坚持要和即将登基的皇太子朱由校一起住在乾清宫，以此要挟群臣。但是这些大臣设计把太子从她手中骗了出来，可是他还是在乾清宫不走。直到太子即位前一天晚上，大臣一起到门口斥责他，就这样，他才被迫离开了乾清宫。
在乾清宫的后边就是交泰殿，取自《易经》中的天地交泰，象征着帝后生活和谐。在殿中央放有25颗宝玺，上方高悬着康熙皇帝御书、乾隆临摹的“无为”匾额。东侧陈设着我国古代人民发明的计时器——铜壶滴漏，西侧陈设着大自鸣钟一座。此在，在每年皇后的生日，皇后都要在交泰殿接受庆贺礼，就连皇太后还有皇帝都要来这里庆贺。在每年皇后到先蚕坛举行仪式的前一天都要在这里检阅采桑工具。
北京故宫英文导游词
FORBIDDEN CITY(紫禁城)
(In front of the meridian gate)
Ladies and Gentlemen:
I am pleased to serve as your guide today.
This is the palace museum; also know as the Purple Forbidden City. It is the largest and most well reserved imperial residence in China today. Under Ming Emperor Yongle, construction began in 1406. It took 14years to build the Forbidden City. The first ruler who actually lived here was Ming Emperor Zhudi. For five centuries thereafter, it continued to be the residence of23 successive emperors until 1911 when Qing Emperor Puyi was forced to abdicate the throne .In 1987, the United Nations Educational, Scientific and Cultural Organization recognized the Forbidden City was a world cultural legacy.
It is believed that the Palace Museum, or Zi Jin Cheng (Purple Forbidden City), got its name from astronomy folklore, The ancient astronomers divided the constellations into groups and centered them around the Ziwei Yuan(North Star). The constellation containing the North Star was called the Constellation of Heavenly God and star itself was called the purple palace. Because the emperor was supposedly the son of the heavenly gods, his central and dominant position would be further highlighted the use of the word purple in the name of his residence. In folklore, the term ”an eastern purple cloud is drifting” became a metaphor for auspicious events after a purple cloud was seen drifting eastward immediately before the arrival of an ancient philosopher, LaoZi, to the Hanghu Pass. Here, purple is associated with auspicious developments. The word jin (forbidden) is self-explanatory as the imperial palace was heavily guarded and off-explanatory as the imperial palace was heavily guarded and off-limits to ordinary people.
The red and yellow used on the palace walls and roofs are also symbolic. Red represents happiness, good fortune and wealth. Yellow is the color of the earth on the Loess Plateau, the original home of the Chinese people. Yellow became an imperial color during the Tang dynasty, when only members of the royal family were allowed to wear it and use it in their architecture.
The Forbidden City is rectangular in shape. It is 960 meters long from north to south and 750 meter wide from east west. It has 9,900 rooms under a total roof area 150,000 square meters .A 52-meter-wide-moat encircles a 9.9-meter—high wall which encloses the complex. Octagon —shaped turrets rest on the four corners of the wall. There are four entrances into the city: the Meridian Gate to the south, the Shenwu Gate(Gate of Military Prowess) to the north, and the Xihua Gate(Gate of military Prowess) to the north, and the Xihua Gate(Western Flowery Gate )to the west ,the Donghua (Eastern Flowery Gate) to the east.
Manpower and materials throughout the country were used to build the Forbidden City. A total of 230,000 artisans and one million laborers were employed. Marble was quarried from fangshan Country Mount Pan in Jixian County in Hebei Province. Granite was quarried in Quyang County in Hebei Province. Paving blocks were fired in kilns in Suzhou in southern China. Bricks and scarlet pigmentation used on the palatial walls came from linqing in Shandong Province .Timber was cut ,processed and hauled from the northwestern and southern regions.
The structure in front of us is the Meridian Gate. It is the main entrance to the forbidden City. It is also knows as Wufenglou(Five-Phoenix Tower). Ming emperors held lavish banquets here on the 15th day of the first month of the Chinese lunar year in hornor of their counties .They also used this place for punishing officals by flogging them with sticks.
Qing emperors used this building to announce the beginning of the new year. Qing Emperor Qianglong changed the original name of this announcement ceremony from ban li(announcement of calendar)to ban shou(announcement of new moon )to avoid coincidental association with another Emperor` s name, Hongli, which was considered a taboo at that time. Qing Dynasty emperors also used this place to hold audience and for other important ceremonies. For example,when the imperial army returned victoriously from the battlefield ,it was here that the Emperor presided over the ceremony to accept prisoners of war.(1)