Duong Lam is built of laterite because the village sits on it. Laterite is an iron-rich layer of weathered soil found just under the fields around Son Tay; it is soft enough to cut into blocks while damp and hardens once it dries in the air, which made it the cheapest strong building stone for miles.
Families used it for everything that had to last: house walls, courtyard walls, gates, wells and the lanes between them. Its pitted, rust-brown surface is what makes Duong Lam look like nowhere else near Hanoi.
Read the walls with someone who grew up between them
Your guide explains how the blocks were cut, laid and repaired, house by house.
★Duong Lam Half-Day Private TourThe laterite lanes, a 400-year-old house and a che lam kitchen, with your own guide · About 5.5 hoursSee the tour →Duong Lam & Thay Pagoda Day TourDuong Lam in depth, lunch cooked in an old house, then the pagoda where water puppetry began · About 9 hoursSee the tour →What laterite is
Laterite forms where heat and heavy rain wash most minerals out of the soil and leave iron and aluminium behind. The result is a porous, honeycombed layer, reddish when fresh and darkening to brown and almost black with age and moss.
Around Son Tay it lies close to the surface. The same material built Son Tay citadel in 1822 and the steps of Tay Phuong Pagoda, which is why the whole western edge of Hanoi has a laterite look.
How the walls were built
Blocks were cut to size while still moist, left to harden, then stacked without plaster. Joints were filled with mud or lime mortar, and many walls were never rendered, so each block shows its holes and colour. Large houses have laterite walls with timber frames inside; gates and wells are laterite from top to bottom.
| Where you see it | What to look for |
|---|---|
| Courtyard walls | Rough blocks of different sizes, moss in the joints, no plaster |
| House gates | Laterite pillars under a small tiled roof |
| Wells | Round shafts lined with laterite, rims worn smooth |
| Lanes | Walls on both sides, paved with old red bricks set on edge |
The fishbone lanes
Mong Phu’s lanes branch off a main road like the bones of a fish, each side lane closed by laterite walls. The layout kept houses close, shaded and easy to defend, and it is why a short walk here feels like a maze.
See the best-kept laterite houses
Our half day walks the oldest lanes of Mong Phu and goes inside a house built in 1649.
Duong Lam Half-Day Private TourAbout 5.5 hoursSee the tour →Duong Lam & Thay Pagoda Day TourAbout 9 hoursSee the tour →Laterite today
Quarrying new laterite is now restricted and old blocks are prized, so families repairing a wall often reuse stone from elsewhere in the village. Some newer houses copy the look with cement; your guide can show you the difference in a few seconds.
Questions people ask
What is the red stone in Duong Lam?
Laterite, an iron-rich weathered soil cut from under the local fields and dried into building blocks.
Why are there holes in the walls?
Laterite is naturally porous; the holes are where softer material washed out as it formed.
Is laterite only found in Duong Lam?
No, it is common around Son Tay and in parts of central Vietnam, but Duong Lam is the best-preserved village built of it.
Walk the laterite lanes with a guide
Car, licensed guide, ticket and tastings in one group price, free to cancel until 3 days before.
★Duong Lam Half-Day Private TourThe laterite lanes, a 400-year-old house and a che lam kitchen, with your own guide · About 5.5 hoursfrom$45/ person›
Choose your group size · price is the group totalSolo traveller$165BOOK →2 guests$170BOOK →3 guests$175BOOK →4 guests$180BOOK →See the full tour page →Duong Lam & Thay Pagoda Day TourDuong Lam in depth, lunch cooked in an old house, then the pagoda where water puppetry began · About 9 hoursfrom$93/ person›
Choose your group size · price is the group totalSolo traveller$275BOOK →2 guests$305BOOK →3 guests$340BOOK →4 guests$370BOOK →See the full tour page →Building history summarised from local heritage sources, checked September 2026.