Travel time from Singapore to Ban Pong 3.5km by train was about 5 days then if they walked 2 days to Kanchanaburi 50km from then if the men walked (some went by boat or truck) to Kinsaiyok 171km maybe about 5 -6 days assuming 20 - 25 kilo a day. Though we don't know if they stopped for a rest day or any other reason, I have read accounts from camp commanders in Chungkai and Tha Makham of large groups of Dutch Soldiers marching through their camps to areas further up the railway in early 1943.


The main work area for Group 4 was between Tha Sao and Kinsaiyok and Group 6 Kinsaiyok to Tha Khanun which includes Kui Yae 190km the men from Group 2 worked further up the railway from Tha Khanun after they had finished up to Wang Pho also the men from F Force in that area up to the border the Dutch Web Site is a little inaccurate that is why Group 6 has ??.


What you have to remember is that there are no hard and fast rules for men working on the railway men were sent where the Japanese wanted them Group areas are only where the majority of the men in the Group worked there are always exceptions.

Thailand-Burma Railway Centre