Occupying 958 km² in Sai Yok District of Kanchanaburi Province, 100 km northwest of the city, Sai Yok National Park is part of the western forest area, which covers 18,730 km² and includes 19 protected areas between Myanmar and Thailand. The park is popular with local and foreign tourists and is known for its waterfalls, caves, historic sites and raft houses on the River Kwai.
The mountainous areas of the park are covered with deciduous and dry evergreen forests, mostly mixed with bamboo. The lower areas along the River Kwai are occupied by teak forest, which was cut down during the Japanese occupation of Thailand, but was later replanted in 1954. The highest point in the park is 1,328 meters and is on the border with Myanmar.
Among the mammals found in the park are elephants, gibbons, macaques, Malayan porcupines, fat loris, serows, muntjacs, Indian zambars, wild boars, and many others. The park is also home to a small population of tigers.
Thailand has two species of mammals that are considered the smallest in the world. One is a rare species of bat called the porcine bat (Craseonycteris Thonglongyai), which can be found in a limestone cave near the Sai Yok Visitor Center.
Locally, this species is named after the Thai biologist Kitty Thonglongya, who first discovered it in 1973. These bats weigh about 2 grams, their body length is 2.5-3 cm, and their wingspan is up to 10 cm.
Another unique and interesting species found in the park is the king multicolored crab (translated from Thai as Poo Rachinee) with red, white and blue shells. It was discovered in 1983.
The chances of seeing some interesting animals around the visitor center are quite rare because it is a commercial area. Striped varans and muntjacs are the only animals seen along the river, if you're lucky. Most of the unusual species live in remote areas along the Myanmar border.
The visitor center area is located on the northeastern edge of the park, 19 km north of Adowa Fire Pass. The entrance fee is 300 baht for adults and 200 baht for children. The sights around the visitor center are not particularly impressive: small waterfalls and small caves.
However, while many of Thailand's large and popular national parks require guides to walk most of the trails, Sai Yok has several well-maintained trails with clear signs that visitors can walk them on their own. What is a must-do is to visit the Dao Dung Cave, which can be reached by boat, sailing 6 km north along the river and hiking the rest of the way uphill for 1.5 km.
There are bungalows and raft houses in the park, as well as tents available for rent at the visitor center (see Attractions below for more information). Several short trails lead to various iconic and historic sites.
The park has three seasons: the rainy season from May to October, when the waterfalls are most impressive and the forests are alive. The cool season is from November to February, with heavy fog and cold weather. December through February is the driest time of year, but water levels in rivers and waterfalls are still high. The hot season is March through May, and there is less water in the waterfalls, but it is much clearer. The average annual temperature is about 15-30°C.
Below you will find more information about the main attractions. Like many other popular parks, Sai Yok is very crowded on weekends and holidays.
Sai Yok sights
Camping and visitor center
The visitor center is located 100 km northwest of Kanchanaburi, 19 km north of Adowa Fire Pass and 3 km from Highway 323 along the River Kwai Noi. The visitor center offers camping, bungalows, private raft houses, grocery stores, restaurants (including floating) and many attractions that can be easily and quickly reached on foot.
There are several bungalows in the administration headquarters area for both 4 and 30 people. While some bungalows are built a few hundred meters from the main buildings, others are a couple of kilometers away, so check the DNP website carefully to see which bungalows you are going to book.
Prices range from 800 to 3,000 baht, with a significant discount when booking on Mon-Thursday. Bungalows can be booked on the DNP website in advance. Since the money transfer must be made within 2 days and transfers from abroad take longer, reservations can only be made from Thailand. Payment can be made at 7-Eleven chain stores or banks.
Despite being in a national park, the raft houses on the river are private, with better quality accommodations and better views than the bungalows.
The campsite is quite spacious, tents and accessories can be rented at the tourist center from 270 baht per day. Parking with your own tent costs 30 baht per day.
There are several short trails of up to 2 km in length near the visitor center, leading to caves, the remains of the famous "Road of Death" bridge, a spring, the riverbank and waterfalls. No guide is required to walk these trails.
River Kwai Noi
Kwai Noi is a tributary of the River Kwai, the main river that runs through the eastern part of the national park. Several raft houses stand on the river with good views of the park, one of the popular attractions of Kanchanaburi province. You can rent a boat for about 400 baht for half an hour to travel on the river.
Sai Yok Yai and Sai Yok Lek Falls
Two small waterfalls flow into the River Kwai Noi from adjacent streams. Sai Yok Yai is right by the suspension bridge next to the visitor center, and Sai Yok Lek is 300 meters downstream. There are viewing platforms on the opposite side of each waterfall with a good view, both of which can be reached on foot from the other side of the suspension bridge. The stream is most impressive during the rainy season beginning in June.
Both waterfalls are beautiful, but on some websites their beauty and size are too exaggerated, leading to the disappointment of some international tourists visiting the park.
Sai Yok Noi Waterfall
This limestone waterfall is located just outside the national park, just a few kilometers north of the Nam Tok (Thai for "waterfall") railroad station, the terminus of the historic Road of Death line.
The waterfall, originating from a spring, flows through the forest and cascades over limestone rocks. It is much higher than Sai Yok Yai and Sai Yok Lek waterfalls, though with less water, and is certainly more beautiful and more suitable for tourists. The best time of year to visit is the rainy season from June to July. During the dry season the water flow will be less, but still the falls are worth a visit.
From Kanchanaburi there are regular buses from 6:45 to 18:00, the trip itself takes about 2 hours. It is also possible to take the train from Kanchanaburi for 17 baht at 6:11, 11:00 and 16:37, which returns at 5:25, 13:00 and 15:15. There are many restaurants and stores along the road.
There are many caves in Sai Yok National Park. There are four small caves already in the immediate vicinity of the visitor center. Please remember to bring a flashlight if you want to visit them.
Dao Wadong Cave
This cave is 100 meters deep and was discovered in 1972. You can reach it by boat, traveling 6 km north of the tourist center along the river and 1.5 km up the mountain on the west side. The cave has 8 cavities that consist of rock, stalagmite and stalactite formations. In rainy and cold seasons you can see the bats flying out before the sun goes down.
Cang Cao Cave
It can be quickly reached on foot via a 2 km trail from the visitor center. This cave is home to one of the world's smallest mammal species, the very rare hog-nosed bat. This species weighs about 2 g, with a body length of about 2.5-3 cm and a wingspan up to 10 cm. The trail to the cave also passes at the base of the "Road of Death" bridge.
Wang Badan Cave
A small two-level cave, 500 meters deep, located in Erawan National Park, which can be reached from Sai Yok Noi Waterfall. Behind the waterfall there is a sign indicating the direction, and the trail itself stretches for 3 km. On the upper level are cavities with beautiful stalagmites and stalactites. A spring runs through the last of them.
One of the most impressive caves in the national park is 500 meters deep, with a small entrance, but with huge cavities filled with large stalactites and stalagmites. The cave is on the west bank of the river and is easily accessible from the nearest house by raft or boat on the river. If you want to get there by car, use the bridge near the train station 20 km to the south and follow the signs.