Lillooet is a small community (pop. 2000) located towards the eastern end of Highway 99, in a mountainous area that also happens to be very dry in places.
The valley floor is near desert-like, with cacti (yes, seriously) and sagebrush scattered grassland. It's not a landscape that many people would associate with Canada! In the summer months, expect hot temperatures (28-30c is the average).
As the largest place between here and Kamloops, be sure to stock up on supplies and gas in Lillooet as needed.