BC’s South Central Interior
This area is mainly in the Interior Plateau volcanic and sedimentary region, or part of the Intermontane Belt and part of the Omenica Belt. See The Building of British Columbia post. It is also, the Thompson River Valley region with the north arm and the south arm of the river meeting in the area of Kamloops making Kamloops the obvious choice as the main hub for human activity in this area. It is dry and hot in summer and cold in winter with precipitation falling mainly in the surrounding mountains. The area includes Lillooet to the west, includes part of the Fraser River where the Thompson river runs into it, Merritt to the south, east to the Shuswap Lake area, and north up to Clearwater and Wells Gray Park. The Secwepemc First Nation are the main First Nation people living in this area, to my understanding. European’s first interest in the area was for fur and gold, and a fur trade post was build in 1812. Not much gold was found. The main economic activities in the area today are: ranching and farming, forestry, mining, tourism and people retiring to the area. When the Coquihalla highway was built, it went to Kamloops and Kamloops became a junction point to go north along highway #5 (South Yellowhead) to Jasper and on to Edmonton and east along highway #1 (Trans-Canada) to Banff and onto Calgary.
This area include the Nicola Valley which is in the rainshadow of the Cascade and Coast mountain ranges making the area quite dry. The Nicola river flows from the northwest of Kelowna into Nicola Lake and empties into the Thompson River. The city of Merritt is the largest community in this area.
The North Thompson River originates from the Caribou Mountains west of Valemount. The Murtle river drains into the Clearwater river which drains most of Wells Gray Park, and then flows into the North Thompson River.
North Thompson River near Avola (smoky due to wildfires) Helmken Falls and Murtle River North Thompson River coming into Kamloops
The South Thompson river originates at the outlet of Little Shuswap Lake by the town of Chase. Shuswap Lake drains into Little Shuswap Lake via Little Shuswap River. Lillooet is west of Kamloops and is situated by the Fraser River. It also is a very dry area and has a long growing season. It is an important location for Aboriginal history and culture, as it is one of the oldest continuously inhabited sites on the continent. This area is home to the St’at’imc people, also to the best of my understanding.
References: McGillivray, B. 2011. “Geography of British Columbia, People and Landscapes in Transition” 3rd Ed. UBC Press. and Wikipedia