Introduction
The Factory
Hau Yong Seng (sometimes spelled “Hao Yong Seng”) is a historically significant, family-run business in Bangkok, producing homemade soy sauce. Operating for over 100 years and spanning several generations, it stands as a rare surviving example of traditional craftsmanship in modern Bangkok just waiting to be explored.
The factory (open 08:00-18:00 Mon to Sat), which resembles a large house, is renowned for maintaining its original recipe and a slow, time-honoured soy sauce production process. A single batch can take up to six months to complete, relying on natural fermentation methods, often involving exposure to the sun. As far as is known, it remains the only homemade soy sauce producer in Bangkok, underscoring its unique and preserved heritage.
Hau Yong Seng is situated on the Bangkok Yai Canal (Khlong Bangkok Yai), in an area that was once a vibrant economic hub. Historically, Khlong Bang Luang was the original name for this same waterway, a name still used today when referring to the community along its banks.
The Café
In recent years, a portion of the old factory has been transformed into the chic Hau Yong Seng Café (09:30-21:00 every day). Here, patrons can enjoy a wide variety of drinks and meals, some featuring their distinctive soy sauce. While the café sometimes attracts a younger crowd keen on photographing themselves and their refreshments, most visitors tend to stay within the café’s modern confines, rarely venturing into the working factory area itself.
The Journey
The walk to the Hau Yong Seng Soy Sauce factory, traversing both the Bangkok Yai and Thon Buri Districts, is an adventure in itself. It leads you through a captivating network of side alleys and lanes, where you’ll discover a slice of authentic Bangkok. Here, residential homes, some beautifully preserved old wooden structures, stand beside a variety of small, independent businesses—from textile workshops to busy motorbike repair shops. The route further enriches your experience by guiding you through a charming Muslim quarter, featuring a serene mosque, and even crosses a working railway line. This all combines to create an unforgettable insight into the city’s unique atmosphere and its people’s culture.
So join me and explore the sights, sounds, and flavours of this off-the-beaten-path neighbourhood. Wander through alleys and streets, where you can witness a slower pace of life, connect with the local culture, and find a quieter, more authentic hidden Bangkok away from the main tourist trails.
Get your camera ready! You never know what unique moments you will come across. This route offers several photographic opportunities highlighted by the camera emoji 📷 throughout the post. Let’s dive straight in.
Highlights
- Walking through Bangkok Yai District
- Hau Yong Seng Café
- Hau Yong Seng Soy Sauce Factory
- Train tracks outside Wongwian Yai Station
- Walking through Thon Buri District
Directions
This route starts at Itsaraphap MRT station and ends at Pho Nimit BTS station. For the most part, you will be walking along narrow lanes and alleys with many interesting side turnings to explore if you wish. Roughly halfway there is a short section following a main road along a bridge over the Khlong Bangkok Yai, and although this is noisy, there are some lovely views along the canal. The total distance is about 4.5 km.
The superscript numbers in the step directions below link to the map at the end. To view the map legend or follow the route in Google Maps, simply click the icons shown here, in the map header.
View the map legend.
Follow the route in Google Maps.
Walking through Bangkok Yai District
Step 1
Make your way to Itsaraphap MRT station and take exit 2. At ground level, turn 180°, walk back about 20 m and take the second alley on the right. Walk about 50 m, go over a canal and under an arch, then turn left in front of Wat Ratchasittharam Ratchaworawihan 📷 (it is worth exploring this extensive temple and outbuildings).
Step 2
Follow the road left for 50 m and turn right around the corner of the temple. Continue following the road for 50 m then turn left between temple buildings.
Step 3
Walk 30 m and pass through a gate and cross a canal on a small bridge. The canal was undergoing renovation in July 2025 and nearly completely covered by metal girders and wood planking.
Step 4
Go straight ahead 100 m to the T-junction and turn right. This is an interesting street to explore with shops and small businesses. 📷
Step 5
After 50 m, turn left. You are now walking along a residential lane with shops and small businesses, like textile workshops and motor repair shops. 📷
Hau Yong Seng Café
Step 1
After 150 m ignore the sign to the Hau Yong Seng car park, which is just before the end of the lane.
Step 2
Continue on for 20 m to the canal.
Step 3
Turn right and you’ll see the Hau Yong Seng Café entrance.
Step 4
The café has views over the canal with old buildings on the opposite side. You can watch the longtail boats go speeding by while sitting on the outside terrace. There is also an air-conditioned room available. 📷
Hau Yong Seng Soy Sauce Factory
Step 1
To reach the factory walk through the café terrace1 and you will see vats of fermenting soy beans outside.
Step 2
You can enter the factory through a plastic strip curtain door. Mind your footing inside as the floor is uneven. Inside and outside the factory you can see the many different stages in the fermentation process and production of the soya sauce. 📷
Train tracks outside Wongwian Yai Station
Step 1
Come out of the café and walk back up the lane to the junction with the road. Turn left and walk 400 m over two small canals (look out for some old wooden houses and interesting alleyways on both sides). 📷Follow the road as it bends left and then right. After a further 50 m, turn left down a narrow lane.
Step 2
After 400 m, the lane becomes a narrow alley. Continue 20 m until you come out into a lane. Turn right.
Step 3
Walk 200 m to the main road, turn left and cross the Bangkok Yai Canal by the road bridge. There are great views along the canal from the bridge 📷 and this is the boundary between Bangkok Yai and Thon Buri districts. On the far side, you will see a footbridge over the main road. Use it to cross the road.
Step 4
Go down the steps to the left.
Step 5
Double back along the main road then turn left into a side road at the traffic lights.
Step 6
Walk 100 m down the side road and take Thoet Thai Soi 5, the second lane on the left.
Step 7
After 50 m, follow the alley to the right.
Step 8
Then after 30 m, follow the alley to the left.
Step 9
Continue straight ahead for about 100 m and cross over a partially covered canal.
Step 10
Continue straight ahead for 50 m to the T-junction and turn right.
Step 11
After about 100 m turn left at the T-junction.
Step 12
Follow the alley left then right and after 20 m you will see the railway line.2 This line is on the route to Mae Khlong Railway Market.
Step 13
With care, you can walk alongside the railway tracks; indeed, local people use it as a thoroughfare in places. The train schedule for Wongwian Yai SRT Station might give you an opportunity to photograph a train squeezing between the trees and houses. 📷
Walking through Thon Buri District
Step 1
Continuing from the railway crossing in step 12, after 50 m the alley turns right. At this point, go straight ahead into a narrow alley.
Step 2
After 20 m, turn right at the T-junction.
Step 3
200 m further on, turn left. This is a predominantly Muslim community3 with a nearby mosque and some old wooden houses. 📷
Step 4
After 50 m follow the alley to the right then after 40 m take this left turn.
Step 5
Walk 40 m and turn right over a small drainage channel.
Step 6
Walk alongside the drainage channel for about 150 m and then turn left at the T-Junction.
Step 7
After 70 m follow the lane as it turns left.
Step 8
In 50 m, turn right and you’ll see the Pho Nimit BTS station ahead. The nearest entrance is just to the right.
Map
Wrapping up
Ultimately, this journey was more than just a tour of a soya sauce factory; it was a layered experience that captured the true essence of two of Bangkok’s neighbourhoods. The rich, salty aroma of fermenting soybeans soon gave way to the scent of coffee and food from the café, all set against a backdrop of deep-rooted traditions.
Walking through the local streets and winding alleyways, each step revealed a new story—a bustling food stall, a family gathered outside a home, a splash of vibrant street art, and the thrilling sight of trains passing impossibly close by. This was a glimpse into the heart of Bangkok, a city where industrial history, modern life, and a strong sense of community exist side by side, creating a truly unforgettable tapestry of sights, sounds, and flavours.
As always if you find any errors in this post I would be very grateful if you would drop me a comment below.
Best wishes
Derek
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