After Tibet and Nepal, the bright lights of Bangkok were a bit of a shock to the system, which was cured by a trip up into the hills north of Chang Rai.
We took a boat out of Chang Rai and travelled west. At one of the village stops, we saw an elephant. The owner offered to take us up to a Karen hill tribe village, where we could stay the night.
The Karen people are an ethnic group native to the mountainous border regions of Burma (Myanmar) and Thailand. The Karen people have several subgroups, including the Sgaw, Pwo, Karenic, and others. The region you mentioned, Chiang Rai, is a province in northern Thailand, and it is home to various ethnic groups, including the Karen.
The elephant took us on a seven-hour trek up to one of the hill tribe villages in the days before Christmas in 1987. The elephant knew the way, so we were not troubled by the guide, who vanished after about twenty minutes. The experience of being alone with an elephant in the jungle was one that I could recommend to anyone.
Our guide reappeared twenty minutes before we arrived in the village.