The North Gate of the Citadel of Hanoi was built in 1805, and today is the only remaining gate to the Hanoi Citadel, which itself was built during the Ly Dynasty and dates from 1010 AD.

The citadel was the seat of the Vietnamese court until 1810, when Hue became the capital city (fig.). Under General Giap, the North Vietnamese military command had its HQ in the citadel, which was by then largely destroyed by the colonial French. The watch tower still bears the scars of cannons fired from French battleships in 1882.

The gate, which is topped with a tetrahedron watch tower, was built in brick, with rectangular edges and an arched doorway. It has two heavy wooden doors, that run on copper wheels and that measure ​12m² each, whilst their combined weight is about 16 tons.

Above the archway is a stone slab in traditional Chinese script that reads, from right to left: zheng bei men (正北門), which means ‘Main North Gate’, the literal translation of which is used for the Vietnamese name, i.e. Chính Bắc Môn.