Ngự Triều Di Quy Communal House (Cổ Loa Communal House)

The communal house stands on a 2,530 m2 plot near the center of the Inner Citadel, about 300 m east of the An Dương Vương Temple, adjacent to the Bà Chúa Shrine to the west and Cổ Loa Pagoda (Bảo Sơn Tự) behind it to the north. According to legend, the site where the communal house was built was formerly An Dương Vương's Thiết Triều Palace. The communal house worships An Dương Vương as its tutelary deity, with Cao Lỗ Hầu as a co-deity—a talented general who made the magic crossbow and a loyal minister who fought and died heroically defending Âu Lạc. The four characters “Ngự Triều Di Quy” are inscribed on the altar cabinet in the rear sanctuary. This name is also used to distinguish it from other communal houses in present-day Cổ Loa Commune that worship King An Dương Vương (throughout Vietnam), such as Mạch Tràng, Sằn Giã, Cầu Cả, and Thư Cưu.

The entire relic complex is surrounded by a wall. The communal house has a two-tiered gatehouse (nghi môn) built and plastered with a roof imitating tubular tiles, with three entrances: one main gate and two side gates connected to the wall, forming a front partition; on the left, a path leads straight to the front of the Shrine. All are simply built and plastered.  The present communal house was inaugurated on March 12 in the third year of Thành Thái (1891).

From the gatehouse, across a large courtyard paved with Bát Tràng bricks, one reaches the main communal house; on the left is Mỵ Châu Shrine, and on the right is the guest house, newly restored in 2004–2005.

Cổ Loa Communal House is a fairly large structure with a layout in the shape of the character “đinh” (or a 'chuôi vồ' plan) comprising five bays, two side wings, and a rear sanctuary. 

The main communal house is 30 m long and 14 m wide; it is a structure with a lim wood frame and a roof covered with mũi hài tiles, with four curved roof corners, looking very imposing. The roof-frame structure follows the “giá chiêng chồng rường” style, with column bases set on blue stone blocks. The main columns are quite large, 5.5 m high and 0.5 m in diameter. The rear sanctuary is separated from the main communal house by a set of folding doors, at the center of the rear sanctuary. Between the main columns stands a large altar cabinet. Right above the cabinet are carved four Chinese characters “Ngự Triều Di Quy”. Inside the cabinet is placed a “throne” draped with a royal yellow robe, worshiping King An Dương Vương.  Below is an altar with a memorial tablet for General Cao Lỗ - Quan Thái Úy Phụ Quốc, and memorial tablets for the civil and military mandarins of the Âu Lạc court. The carvings on the wooden structure of the communal house are not numerous but quite beautiful, concentrated on the đầu dư, con rường, kẻ, and ván nong. On the architecture of the communal house there are many panels of intricate, elaborate, and vivid openwork and relief carving. In particular, the communal house has a set of gilded and lacquered ceremonial doors (cửa võng), a unique work of art with themes of the four sacred creatures and four noble plants, demonstrating the talent and creative intelligence of the old craftsmen. This set of ceremonial doors dates from the major restoration in Thành Thái Quý Mão spring (1903), recorded in a small recessed panel above the ceremonial doors. In addition, the communal house has preserved valuable relics such as a worship throne, memorial tablets, horizontal plaques, couplets, an altar table, and the Eight Treasures (bát bửu)...

Based on construction methods and carving art, the communal house may have been first built around the late 18th to early 19th century; that is, before it was rebuilt, the old communal house was nearly 100 years old. According to folk legend, the communal house was purchased from Bồng Mạc Village (now in Liên Mạc Commune, Mê Linh District, Hà Nội City). This was a large and beautiful communal house that the villagers bought and transported back by river. When rebuilding it, the villagers had to add some structural components. In the early 20th century, there was a major repair of the communal house's roof. Under the quá giang of the central bay of the communal house, the date “Thành Thái tam niên” (1891) of this restoration is still recorded. After that, there were several minor repairs, such as in the first year of Bảo Đại (1926), when the rear sanctuary was repaired. Over time and through historical events, some architectural parts of the communal house were damaged or lost (according to elderly locals, after 1954 all the floorboards were removed). In 1993–1994, some large components of the roof truss, such as the subordinate columns and veranda columns, were replaced, and the roof was repaired. In 1999–2000, on the occasion of the 990th anniversary of Thăng Long–Hà Nội, the Hà Nội City People's Committee restored the entire communal house floor and the surrounding folding doors. In 2005, work continued on repairing the gatehouse, enclosing wall, garden courtyard, paths, and landscape of the Ngự Triều Di Quy Communal House–Mỵ Châu Shrine area; the communal house's hữu vu building was also reconstructed on its old foundations.

Ngự Triều Di Quy Communal House was ranked as a National Historical and Cultural Relic in 1962, and in 2012 it was ranked as a Special National Historical Relic.