Discover the wonder hidden behind Vietnam's unique stone citadel.

The Ho Dynasty Citadel is not only the largest stone heritage site in Vietnam but also a testament to peak engineering skills, with many mysteries that remain unexplained to this day.

The citadel was built in just three months. Records show that the entire massive structure was erected in about three months in 1397, an astonishing speed for its scale.

The stones used to build the citadel weighed tens of tons. Many blocks of stone, weighing 10–26 tons, were fitted together tightly without any binding material, demonstrating the high level of technical skill of the ancient people.

The stone-laying technique is rare. The Ho Dynasty citadel uses an extremely skillful method of stone arrangement; the meticulously cut and shaped stones are stacked tightly together without mortar, creating vertical stone walls with alternating layers that are very solid.

The city gates were built along astronomical axes. The South Gate of the Ho Dynasty citadel was built slightly off-center to align with astronomical observation axes, reflecting the cosmological thinking of the Tran-Ho period.

The gate arches are built in a "grapefruit segment" style. The stones used to build the city gate are precisely carved and fitted together in a "grapefruit segment" pattern, without the need for mortar, creating extremely sturdy and load-bearing arches, a testament to superior stone construction techniques.

Many valuable artifacts have been found. Ho Citadel is an important archaeological site where many valuable artifacts have been discovered, such as stone bullets, pottery, sculptures, etc.

It was the largest stone-built citadel in Vietnam. No other historical citadel in Vietnam, before or after the Ho Dynasty, was built with such large stones on a scale comparable to the Ho Dynasty citadel.

A world-class landmark. In June 2011, the Ho Dynasty Citadel was recognized by UNESCO as a World Cultural Heritage site. This is Vietnam's fifth World Cultural Heritage site, after Hoi An Ancient Town, Hue Imperial City, My Son Sanctuary, and Thang Long Imperial Citadel.

We invite our readers to watch the video : Ha Long Bay - A magnificent World Natural Heritage site / Quang Ninh TV

Source: https://khoahocdoisong.vn/kham-pha-su-ky-vi-an-sau-toa-thanh-da-co-mot-khong-hai-viet-nam-post2149075188.html