The Imperial Enclosure or Imperial City is a citadel-within-a-citadel, housing the emperor’s residence, temples and palaces, and the main buildings of state, within 6m-high, 2.5km-long walls. What’s left is only a fraction of the original – the enclosure was badly bombed during the French and American Wars, and only 20 of its 148 buildings survived. Expect a lot of broken masonry, rubble, cracked tiling and weeds as you work your way around, but it's a fascinating site and easily worth half a day.

At a leisurely stroll, many of the less-visited areas are highly atmospheric and sublime. It's best to choose a day with decent weather, with late afternoon (when there are fewer visitors and the sun is setting) a superb time to visit. There are little cafes and souvenir stands dotted around. It's best to approach the sights starting from Ngo Mon Gate and moving anticlockwise around the enclosure. Restoration and reconstruction are ongoing.

Built on a small hill overlooking the Song Huong (Perfume River), 4km southwest of the Citadel, this seven-story pagoda is an icon of Vietnam and as potent a symbol of Hue as the Citadel. The 21m-high octagonal tower, Thap Phuoc Duyen, was constructed under the reign of Emperor Thieu Tri in 1844. Each of its stories is dedicated to a manushi-buddha (a Buddha that appeared in human form). Visit in the morning before tour groups show up.

Thien Mu Pagoda was originally founded in 1601 by Nguyen Hoang, governor of Thuan Hoa province. Over the centuries its buildings have been destroyed and rebuilt several times. Since the 1960s it has been a flashpoint of political demonstrations. To the right of the brick pagoda tower is a pavilion containing a stele dating from 1715. It’s set on the back of a massive marble turtle, a symbol of longevity. To the left of the tower is another six-sided pavilion, this one sheltering an enormous bell (1710), weighing 2052kg and audible from 10km away. Beyond the pagoda tower is a gateway, on the upper floor of which sits an effigy of the Celestial Lady (Thien Mu), who the pagoda is named after.

Above the central portal is a board with the Chinese characters (literally 'Divine Old Woman Temple'), in honor of the presiding deity of this plot of land. The temple itself is a humble building in the inner courtyard, past the triple-gated entrance where three statues of Buddhist guardians stand at the alert. In the main sanctuary behind the bronze laughing Buddha are three statues: A Di Da, the Buddha of the Past; Thich Ca, the historical Buddha (Sakyamuni); and Di Lac Buddha, the Buddha of the Future.