Yueyang Tower, or Yueyang Pavilion (it is indeed a pavilion, but a towering pavilion, hence the alternative designation), one of the Four Great Towers of China*, is situated at the western gate of Yueyang Ancient City, Hunan Province, overlooking Lake Dongting from its perch on the eastern shore of the lake. On the opposite side of Yueyang Tower flows the mighty Yangtze River. It is no accident that Yueyang Tower occupies the strategic position it does, for the tower - or rather, its first simplified version - was originally constructed with a military objective in mind (the original tower was named Ba Ling, after the nearby city of the same name): to monitor the movement of the naval vessels at the Wu State (i.e., the Wu State of the Three Kingdoms (CE 220-280) Period) navy training facility at Lake Dongting during parade maneuvers.
Lake Dongting served namely as the venue for the Wu State's fleet of training ships which were under the command of Lu Su, the famous Wu State military advisor who served as an aide to Zhou Yu - the even more famous Wu State military advisor - during the decisive Battle of Red Cliffs on the Yangtze River, whom Lu suceeded after Zhou's death (to read about the Battle of Red Cliffs and its role in the power struggle that was unfolding between the three warlords who each had set up a separate kingdom, or state (the other two states were the Wei State and the Shu State, though, in the end, the Jin (CE 265-420) Dynasty would emerge as the victor, reunifying China), click here, then scroll to the bottom of the page to the footnote).
In CE 716, during the fourth year of the Kaiyuan (CE 713-741) Reign of Emperor Xuanzong of the Tang (CE 618-907) Dynasty, Yueyang Tower was reconstructed on the site of the original tower. Its beauty and its placement overlooking especially Lake Dongting made Yueyang Tower the object of literary praise. For example, in CE 1045, during the fifth year of the Qingli (CE 1041-1048) Reign of Emperor Renzong of the Song (CE 960-1279) Dynasty, the governor of Ba Ling County, Teng Zijing, invited his friend, ex-chancellor** and 'man of many parts' - including one involving literary flair - Fan Zhongyan, to write an essay in honor of the newly-reconstructed (and renamed) Yueyang Pavilion. The result was the famous hommage "Memorial to Yueyang Pavilion", one of the lines of which is the immemorable admonition to "[b]e the first to show concern about the country's problems, the last to rejoice when those problems are declared resolved" (or the last to declare "mission accomplished", if you will).
The current 20-meter-high pavilion (including its base) with its four pillars made of rot-resistant nanmu trees (Phoebe nanmu, a member of the Laurel family), its three storeys with upturned eaves and its unique construction method*** stems from a major reconstruction in 1867, during the Qing (CE 1644-1911) Dynasty.
There are two other pavilions on the grounds, as well another important historical site nearby. Sanzui ("Thrice Drunken") Pavilion (after a legend about the Immortal, Lu Dongbin, who got drunk here three times) and Xianmei ("Fairy Plum Blossom") Pavilion lie on either side of Yueyang Tower, and to the north of Yueyang Tower lies the the tomb of Xiaoqiao, the wife of the famous Three Kingdoms Period military advisor, Zhou Yu. The picturesque scenery of the site of Yueyang Tower attracted the attention of many distinguished poets of the Tang Dynasty, personalities such as Li Bai, Du Fu, Bai Juyi and Li Shangyin, who wrote odes to the pavilion after spending time here. These works are preserved and cherished, and are on display in the Corridor of Poems and Calligraphy at Yueyang Tower.
Yueyang Tower has long enjoyed the distinction of being the "First Tower under Heaven", an oblique reference to the fact that Lake Dongting itself enjoys the distinction of being known as the "First Water under Heaven." Yueyang Tower is, understandably, the defining landmark of Yueyang City.
* The Four Great Towers of China are: Yellow Crane Tower, the Pavilion of Prince Teng, Yueyang Tower and Penglai Pagoda (note the different designations, though they are each considered a tower, given their height).
** The position of chancellor in China is not comparable to any position known to Western culture. Fan Zhongyan was the chancellor of all of China. It is a bit like being an American president's White House Chief of Staff, National Security Advisor, and Joint Chiefs of Staff, all rolled into one. The chancellor was the supreme advisor to the Emperor in matters of state and military affairs. Since Fan Zhongyan took his duties to the state seriously (viz., the famous line from the 'Memorial to Yueyang Pavilion'), he allowed himself to make suggestions about how the state could improve its functioning by appointing individuals based on their intelligence and their merit rather than on other factors. This ruffled a lot of feathers both at court and throughout the country. Fan Zhongyan had left court earlier due to sharp disagreements, but when the state was again in a crisis situation, the Emperor invited him back, where he eventually again managed to ruffle feathers. In the end, the Emperor rescinded many of the changes that his uncompromising chancellor had instituted.
*** The all-wooden Yueyang Tower is held together by a clever system of brackets that does not require nails, bolts, glue or anything of the like. The brackets are instead held in place via an interlocking-joint system referred to as mortoise and tenon ("peg and hole") joinery (think of the way a jigsaw puzzle is held together via interlocking pieces). Besides the four main pillars which support the entire structure, there are twelve additional wooden pillars that support each upper storey, the twelve pillars on the second storey being lighter than the main pillars but sturdier than the twelve pillars on the third, or top, storey.