A guardian of old Thang Long
The temple honors Huyền Thiên Trấn Vũ, a Taoist deity linked to the north and to protection against evil. Ancient Thang Long, the city that became Hanoi, was said to be watched over by four guardian temples, one for each direction. Quan Thanh is the guardian of the north.
Tradition dates its founding to the 11th century, under King Lý Thái Tổ. The buildings you see today come from later rebuilding, but the temple has stayed an active place of worship.
What to look at
You enter through a three-door gate into a quiet courtyard shaded by old trees. Look up at the carved roof ends and the boards written in Chinese characters. Locals come here to light incense and make offerings.
The main reason to come is inside the main hall. A large black bronze statue of Trấn Vũ sits there, cast in 1677 and weighing about four tonnes. Watch for the details: a sword, and a snake and a turtle at his feet. The bronze shines where people have touched it for luck.
When to go
Mornings are calm and cooler, and the light in the courtyard is soft. The 1st and 15th days of the lunar month draw many worshippers. On those days the temple stays open longer and the courtyard fills with incense. Come then if you want to see the temple in use. Choose another day if you prefer quiet.
Combining it with nearby places
Trúc Bạch Lake is 0.3 km away, a good place for a lakeside walk or a cafe stop. Ba Dinh Square (0.7 km) and the Presidential Palace and Stilt House (0.6 km) are a short walk south. The Hanoi Flag Tower is 1.2 km away. A classic morning starts at Tran Quoc Pagoda on West Lake, then a walk to Quan Thanh, then a ride back to the Old Quarter for lunch.