Sai Yok is a pretty district to the north of Kanchanaburi town and is best known for Sai Yok National Park and the nearby Hellfire Pass railway cutting, which was built by POWs during WWII.
Tourists heading to Sai Yok are generally of the discerning type in search of beautiful landscapes rich in forests and mountains. Sai Yok National Park is the main attraction and comes with many miles of excellent trekking along with some stunning waterfalls. Sai Yok Yai Waterfall, which flows into the Kwai Noi River, is one of the main highlights.
Sai Yok also contains an abundance of wildlife including bats, squirrels and deer, along with many species of birds. A little farther afield is Hellfire Pass; the deep railway cutting that was sliced out by weary WWII Allied POWs. You can stay in resorts and raft-houses in Sai Yok district and have a game of golf.
Sai Yok district is accessible from Kanchanaburi by bus, train or hire car. Trains stop at Nam Tok Train Station, not far from Sai Yok Noi Waterfall. Kanchanaburi town itself is 3 hours by road from Suvarnabhumi International Airport in Bangkok, the main Thai air gateway.