The River Kwai is a river in western Thailand, known for its scenic beauty and historical significance. It flows through the Kanchanaburi province and is part of the larger Khwae River system. The river is famous for the Bridge over the River Kwai, which was built during World War II by prisoners of war and forced laborers. The area around the River Kwai is a popular tourist destination, attracting visitors with its lush landscapes and historical sites. The river is also a part of the Erawan National Park, where tourists can enjoy activities like hiking and swimming in waterfalls.