Dien Khanh

Geography

The district lay at the centre of Khánh Hòa, bordered by Nha Trang city to the east, Khánh Vĩnh district to the west, Cam Lâm district to the south and Khánh Vĩnh and Ninh Hòa town to the north^[1]. Its seat, Diên Khánh township, stands 10 km west of the centre of Nha Trang beside National Route 1^[1][5]. Wikidata places the district at 12.260 north and 109.101 east^[7].

National Route 1A, the Nha Trang-Cam Lâm expressway and the North-South railway cross the district, and the Vân Phong-Nha Trang expressway was under construction through it^[1]. The township was recognised as a class IV urban area by Decision 854/QĐ-BXD of 22 September 2010, and Decision 220/QĐ-BXD of 2 March 2021 recognised the whole district, its township and 17 communes, as a class IV urban area of the province^[1].

From prefecture to district

The land was the Diên Ninh prefecture of the Thái Khang garrison; in 1742 the lord Nguyễn Phúc Khoát renamed it Diên Khánh prefecture, of which Phước Điền district, the later Diên Khánh district, was part^[1]. When the Bình Hòa garrison became Khánh Hòa province in 1832 the province had two prefectures and four districts, and Diên Khánh prefecture held the districts of Phước Điền and Vĩnh Xương^[1]. Under French rule the prefecture had three cantons: Trung Châu north of the Cái river, Vĩnh Phước to the south-west and Ninh Phước to the south-east^[1].

After the August Revolution the revolutionary government abolished the prefecture in 1946 and created Diên Khánh district^[1]. From 1950 to 1954 Diên Khánh and Vĩnh Xương were joined as Vĩnh Khánh district; the Republic of Vietnam divided the area at times into the highland districts of Vĩnh Sơn and Vĩnh Khánh and the lowland districts of Cửu Long and Hương Giang, and from 1965 to 1975 the communes of Diên An and Diên Toàn were assigned to Vĩnh Trang district^[1].

Since 1975

After 1975 Diên Khánh was merged with Vĩnh Xương into Khánh Xương district of Phú Khánh province. Decision 49-CP of 10 March 1977 transferred seven communes of the old Vĩnh Xương to Nha Trang and merged the rest of Khánh Xương with Khánh Vĩnh to re-create Diên Khánh district with 24 communes^[1]. Decision 100-HĐBT of 30 September 1981 created Diên Khánh township from Diên Thủy commune and parts of five neighbouring communes, and Decision 189-HĐBT of 27 June 1985 detached seven highland communes to re-establish Khánh Vĩnh district^[1].

When Khánh Hòa was re-established on 30 June 1989 the district had its township and 20 communes^[1]. On 11 April 2007 Decree 65/2007/NĐ-CP transferred Suối Tân and Suối Cát communes, 17,590 ha with 15,324 inhabitants, to the new Cam Lâm district^[1][10]. Resolution 894/NQ-UBTVQH14 of 11 February 2020 merged Diên Bình and Diên Lộc into Bình Lộc, and Resolution 1196/NQ-UBTVQH15 of 28 September 2024 merged Diên Đồng and Diên Xuân into Xuân Đồng, leaving a township and 16 communes^[1].

The communes of 2025

Items 12 to 17 of Resolution 1667/NQ-UBTVQH15 regrouped the township and 16 communes into six communes, which began operating on 1 July 2025^[3]. The township, Diên An and Diên Toàn became Diên Khánh commune, so that the citadel town keeps the name^[3].

Population

The provincial statistical yearbook gives the district 337.6 km² and an average population of 143,420 in 2019, a density of 425 people per km²; Vietnamese Wikipedia gives 336.2 km² and 142,706 people for the same year^[1][2]. Statoids lists an estimate of 134,118 people on 513 km² for 2003^[8], before the 2007 transfer of Suối Tân and Suối Cát, 17,590 ha, to Cam Lâm reduced the district's area^[10]. English Wikipedia repeats the 2003 figures^[9].

The citadel

In 1793, after taking Diên Khánh from the Tây Sơn, Nguyễn Ánh, the future emperor Gia Long, built a fortress there as a forward defence^[5]. The citadel follows the Vauban model of Western Europe: an irregular hexagon of earth walls with a perimeter of 2,693 m and a height of about 3.5 m, enclosing about 36,000 m² and ringed by a moat 3 to 5 m deep and 20 to 30 m wide; of its six original gates four survive, the East, West, Front (south) and Rear (north) gates^[5]. Tuổi Trẻ gives the enclosed area as 3.5 ha and the wall length as 2,600 m^[4]. Both sources pair a wall of about 2.6 to 2.7 km with an enclosed area of about 3.5 ha, which no closed figure can do: a wall of that length encloses many times that area. The figures are reproduced as they are published^[4][5].

The citadel was the political and administrative centre of Khánh Hòa from 1802 to 1945, and it was listed as a national historical and cultural relic in 1988^[4]. In the colonial period the offices of the Nguyễn court stayed inside it while the French services moved to Nha Trang, and it also served as a base of the Cần Vương resistance in the first years of French rule^[5]. Before restoration the district's own offices and a football pitch occupied the interior^[5].

A restoration announced in June 2024 with a budget of about 167 billion VND began in December 2024; by September 2026 the budget had been revised to more than 225.5 billion VND, about 75 percent of the work was complete, with the moat, a pump station, the Rear Gate bridge, roads and drainage under way, and completion was targeted for 2026^[4][6]. The project required clearing nearly 7.5 ha of land from 122 households, of which more than 7.2 ha had been acquired^[6].