Sop Ruak
For the convenience of tourists, the thousands of square miles of the opium growing region has been distilled down to a single point in Thailand at the small village of Sop Ruak, about 9 kilometers (6 miles) from Chiang Saen. This is where the Ruak and Mekhong Rivers meet. South of the Ruak is Thailand, north of it is Burma and east of the Mekhong is Laos.
Sop Ruak is little more than a tourist spot. The riverside road is lined with souvenir stalls. The small Opium Museum in the center of the village is purely commercial, but interesting nonetheless (admission 20 Baht). A lookout at the top of a hill next to the museum affords 'the view' of three countries. The lookout is adjacent to the 1,200 year old temple of Wat Phrathat Phu Khao (literally, 'temple on the hill').
Sop Ruak is usually the embarkation point for speed boat trips which take you up-river a short distance, then down to Chiang Saen, with a stop at a Lao souvenir village on the way. Cost for the trip alone should be around 400 Baht.