Karen or simply Long Neck is a name of a tribe from Myanmar (Burma), but also living in Thailand these days.
Karen women are very characteristic, because they wear several metal rings around their necks, wrists and ankles.
You can visit in Thailand villages where minorities live; however usually it’s not so authentic experience and it’s mostly about buying their hand made products (it also can be interesting at some level…).
Golden Triangle is an area where people used to grow opium, at the boarder or Laos, Myanmar and Thailand.
You can visit the place e.g., while being in Thailand, but I don’t really think it’s worth visiting…
Unfortunately, Thailand is famous for e.g., elephants.
I wrote unfortunately, because many places with animals in Thailand are of quite poor quality, and it’s very sad they exist, and poor animals have to be there.
Of course, you can also find a place own by people who love nature and animals and treat them well; but it’s a challenging task to find this kind of place in Thailand…