Mỹ Sơn: brick walls where no mortar joints can be found

My Son is located in a valley in Duy Xuyen, Quang Nam, approximately 70 km from Da Nang. From the 4th century until around the 13th-14th centuries, the Cham people built dozens of temples and towers here dedicated to the god Shiva. That's nearly a thousand years of continuous construction on the same piece of land — something very few places in the world have managed to do.

What has drawn researchers back to My Son for more than a century is not its scale, since the Cham towers are not as massive as Angkor. What keeps them coming back is the construction technique.

Standing right against the tower wall and looking at it, you can barely see any mortar joints. The bricks fit so tightly together that in many places it seems like the entire wall was molded from a single block. Moreover, the bricks are light, porous, and have withstood the sun and rain of Central Vietnam for hundreds of years without developing moss like modern bricks do.

Many explanations have been attempted: using dipterocarp resin as an adhesive; grinding the brick surfaces and joining them while still damp; or building the entire tower structure first and then firing it as a whole. So far there's still no final conclusion — each hypothesis manages to explain a few of the phenomena while remaining stumped by several others.

What's more notable: during restoration periods, the newly inserted brick sections can usually be told apart right away with the naked eye. The color is different, and over time it deteriorates faster than the old brick. That means after so many years with all sorts of analytical equipment, we still haven't managed to recreate exactly what the craftsmen here achieved more than a thousand years ago.

Mỹ Sơn also bears the scars of the 20th century. In 1969, a bombing destroyed most of Group A, including the A1 tower, which was regarded as the most beautiful structure in the archaeological site. What remains today is only a fragment of what once stood there.

The temple complex was recognized by UNESCO as a World Cultural Heritage Site in 1999.

If you go: take the earliest departure of the day — the valley is sheltered from wind and gets very hot by noon, while mornings are quiet with fewer people. Wear closed-toe shoes, since the paths inside the site are dirt and rocky. There's an electric cart to take you from the entrance in, but you'll still have to walk between the groups of towers.

And if you can, take a few minutes to stand very close to a wall. Touch the spot where two bricks meet. That feeling of not being able to find the mortar line is worth more than any photo taken from a distance.