I understand the main areas of this national park to be mainly savannah and pine trees, very different to the photos in the first couple of posts here! I have a plan to go to Khao Kho end of June so I will fill out this thread more then, but for now this is just about Noen Maprang, and more specifically Ban Mung, which are in Phitsanulok on the edge of the western park boundary. Noen Maprang is 20km point to point from the main attractions of TSL National Park (around Khao Kho area), but if you were driving the shortest route between them would be 146km. Just to get it out of the way, be prepared for even worse dual-pricing than normal. TSL NP is 500 baht compared to 40 for Thais.
From Noen Maprang, travel 7km to Ban Mung. The National Park has a substation here; number 6; at Tham Duan Tham Dao - caves I skipped to avoid the 500 baht thing, plus I read they require a guide which I imagine is extra.
In the centre of Ban Mung there is a bat watching area. Every night before sunset you can wait around here and watch millions of bats fly past. It's a public area; free to enter, with really cool toilets.
Ban Mung Temple has a few caves, look out for this one which starts very cramped but opens up as you get further inside.
It's possible to walk inside about 75 metres. If you walk around the temple grounds you can hear the bats in various caves on the rock face, I think this is where many of the bats come from that you watch flying overhead at the bat watching area. Possibly it might be an alternative place to watch them emerge at sunset.
My favourite attraction at Ban Mung is a really steep climb up to an otherworldly landscape of spiky rocks stretching over 1000s of metres.
The exact coordinates for the turn off the road onto a dirt trail are 16.562415439879523, 100.69700606348 In dry season scooters can use this dirt track. Normal cars can't. I haven't tried it in rainy season but would imagine it gets very muddy. Cars should be left at Wat Ban Mung because there's nowhere to park. The exact coordinates for the trailhead (approx. 600m along the track) are 16.564500064034604, 100.70074101485348
Once you get to the trailhead the route is obvious with ropes and ladders all the way up to the top. You don't need any special climbing equipment though gloves and decent shoes are recommended. Try it in flipflops and the rocks might impale your feet through the rubber. When the organised groups go up they are wearing hardhats.
A person in good shape could get to the top in 20-30 minutes. Most people will take an hour. Once at the top there are various bamboo viewing platforms, the furthest platform is tricky to find the route to and is a further 400 metres (40-80 minutes away, it's slow going across the minefield of spikes), but no need to go that far because the views are great wherever you stand.
Both the first and second summits have flagpoles so you can get your bearings but at the time of writing the second summit's flag is shredded and you can only see the pole.
There is no staff presence so unless you go on a weekend you probably won't see anybody else. I am not sure if permission is supposed to be obtained prior to climbing - there is no national park signage, it looks like the ascent is being organised by a private person/company; they have a sign at the trailhead which I forgot to take a picture of. Perhaps they have an agreement with the national park.
There are makeshift toilets (take your own paper) and it would be a really nice place to camp. I wonder if the platforms up here would be a good place to view the bats... possibly a bit high.
GPS track, starting from the temple: