Read the following passage and mark the letter A, B, C or D to indicate the correct answer for each of the questions.
Famously becoming one of Vietnam's seven UNESCO World Heritage Sites in 1993, the Imperial City of Hue has long been a must-see attraction for tourists visiting a hidden charm of Vietnam. The Imperial City of Hue was actually a walled fortress and palace belonged to the ancient city of Hue which was a capital city of the Nguyen Dynasty for 140 years date back from 1805 until 1945.
The grandeur architecture was planned to be built in 1803 by Gia Long an emperor who founded the Nguyen Dynasty. During 27 years from 1805 to 1832, the Imperial City of Hue was finally completed under the reign of Minh Mang, involving thousands of workers, millions cubic meters of rock and huge volume of burden workload. It is located on the northern bank of Huong River, turning South with total land area of 520 ha. Initially, the fortress was built solely by soil, only to be replaced by bricks afterward. Surrounding the city is the complicated canal system served not only as a protection but also as a waterway with nearly seven kilometers.
There are totally ten main majestic gates leading to the Imperial City of Hue, which can be divided into two main parts excluding houses and mansions: The Citadel and The Forbidden City. The former, the Citadel, served to protect the important palaces inside while the latter was where the emperor and the royal family stayed as well as the court's workplace.
