We visited Doi Inthanon in September. One of the few orgainised tours we did in Thailand. It cost us a reduced price of 1000 baht each which included everything, air conditioned van (with only 4 of us in it), English speaking guide, entry fees and a great lunch. We made 6 stops inluding lunch. 2 waterfalls/gardens, a Karen tribal village, the stupas and the highest point in Thailand.
At the first stop, Wachirathan waterfall, you can quite wet from the spray and it can get surprisingly cold on the mountain, so take some warm clothes. It's very beautiful, as is the third stop at Siribhume gardens.
It was very atmosperic at the King and Queens stupas (Napamaytanidol Chedi and Phra Mahatat Napaphon Bhumisiri), as they were partially in the clouds.
I am glad I went, as I missed going on our first trip to Thailand...it was well worth it!
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