Some 20,000 holidaymakers have swarmed Phu Thap Boek in Phetchabun. outstripping the capacity and facilities of the scenic mountain destination and causing a traffic jam as long as 30 kilometres The main attraction in the area, which tops the Unseen Thailand list, is the panoramic view of the "sea of fog" that can be appreciated from the hilltop at this time of if one can find a vantage point amid the sea of tents. Located 400 kilometres from Bangkok, the destination is also considered not too far from the capital for a weekend visit However, popularity comes at a high price. with unchecked building of resorts many of them illegal and some unsafe, turning green slopes into a veritable eco-slum