Unfortunately the signs are only good at the beginning of the trail, not all trails have English directions. Only Thai. As the Khao Yai National Park is really huge and wide, best recommendation is still to engage a guide (not expensive, but safe) work out with him/her on the route you and family would like to trek, and in the event of heavy rain etc in Dec, how to backtrack or take alternate paths back to shelter. (Dec could be the Monsoon period in Thailand, may hit the area you wanted to go). Keep safe and having a local guide is always safest approach. If you need recommendation for a English speaking guide, ping me. I can recommend you our guide.

We had an incredible two-day wildlife tour with Tontan Travel. They offer trekking as well.

Bonjour, si vous voulez contacter Cedric toute les coordonnées sont disponibles sur le site les Collines de khao yai sinon si besoin je peu vous donner son numéro de mobile étant donner que j'ai effectué un Trek la bas il y à peu. Si toujours d'actualité foncez y c'est incroyable Cedric ainsi que les guides sont au top du professionnalisme vous ne ratée rien.

Depending where you are staying. I was in Bangkok and the tour is actually a full day tour. The journey to the national park also take 2-3 hours but they do stop on the way there to see some other attraction like elephant ride, market etc. So it will be good to allocate a full day if you are planning to visit this place. Since u have a family member that is 70yo then the waterfall is definitely not a good idea because walking to the waterfall there are very steep staircase that you need to take which is not safe for elderly people. The best is you check with the tour agents there and plan the best tour to take.

I agree, a good guide makes the experience. We were incredibly pleased with Ton Tan Travel for two days of private guiding. I strongly recommend them or another guided tour.

yes ,just walking to enjoy the nature.