The 500 Rai Floating Resort on Lake Cheow Lan, Khao Sok National Park, Surat Thani, Thailand. Thais have long known about the beauty of Khao Sok National Park in Thailand s southern Surat Thani province, but the destination is still not very well known amongst travellers from abroad. That s about to change. Atirat Danphattharaworawat, Managing Director of 500 Rai, tells us all about his two amazing resorts.