Doi Inthanon, the roof of Thailand, is Thailand’s highest mountain. Located around 60 kms south of Chiang Mai, this is a prominent mountain at an altitude of 2565 m. Wikipedia has lots of information http://en.wikipedia.org/wiki/Doi_Inthanon, as has http://www.chiangmai-chiangrai.com/doi_inthanon_park.html
Camping is at the base of the mountain, near the park headquarters, among pine trees. It is OK, but no one would return for the campsite. It can get cold, even down at the campsite. The drive up to the summit takes around 50 minutes and gives great views. It is definitely worth a visit if you are in the area, but personally, I would not drive more than a hundred kms out of my way for it.
There is a well organised visitor center at the top, the highest peak in a mighty kingdom, which all feels quite organised, as if focused on a one time visit by otherwordly creatures, perhaps from Uranus or Mars, rather than mere tax paying residents, if you see what I mean, reading between the lines.
Note that there is an escalator here which is operational round the clock! Its a great pity that the same engineers were not involved in the design of some sky stain stations in Bangkok.
I suspect that the park could get very crowded on auspicious occasions, holidays and weekends, but the only time we camped at Doi Inthanon was during a weekday in the rainy season. It poured, and we were sensibly (for others) the only people there.
My rocket fuel, 1 part petrol to 5 parts diesel was very welcome, as we at least got a fire started, using our usual store of dry wood in the truck, and the wet pine wood lying around, which did eventually dry out, after some roasting.
This is just the kind of occasion when you need it, even though every one laughs at me for it. I have an enduring memory of a completely drenched night in the middle of Zaire, when the same thing worked a treat and everyone got a hot meal.