On Friday, July 22nd, 2016 Paññāsāstra International School has organized a one-day Study Tour for students in grade 12th and a group of students in Poster Contest winners to visit various historical sites along national road number 5 from Kandal province to Kampong Chhnang province. The historical sites include Catholic Church, Khlaing Sbek village, Udong Mountain, and Banteay Lungvek. The primary goal of this Study Tour is to bring students for their sight-seeing the Khmer historical sites which left by our great ancestors from the past period particularly Lungvek regime. In addition, we want them to discover the real pictures besides studying in the classroom, so that they can witness and find their ways better to understand Khmer history. Moreover, it motivates students to consecrate their thought to protect and plan future development of these historical sites for the next generation prospectively. Another important thing about this Study Tour is that all students are required to conduct further research about these historical sites and write report for their teacher in history subject.