Tat Ton waterfall is in Kaeng Tana National Park อุทยานแห่งชาติแก่งตะนะ. It’s technically in the SW corner of the park, but there is no fee to get in even though there are staff on duty at the gate. The top of the falls is shallow and easy to walk across but watch out for the many holes. My traveling companion slipped and fell into one of them. Thankfully it only went up to his waist. There are some picnic tables at the parking area and a small store selling food on the other side of the falls if you can walk over the falls.