is located in Ban Pak Chan, Tambon Pak Chan, 80 kms. from the city area or 16 kms. from Amphoe Kra Buri. It can be reached by traveling along the Highway No. 4 (the route to Chumphon) and then turning left at kms. 529-530 to the laterite road fro another 3 kms. Sai Rung which means a rainbow in named according to the splashing figure of the waterfall resulting from the strong hit of the powerful water agains rocks.