The Kootenays are more or less defined by the
Kootenay Land District, though some variation exists in terms of what areas are or are not a part. The strictest definition of the region is the
drainage basin of the lower
Kootenay River from its re-entry into Canada near
Creston, through to its confluence with the
Columbia at
Castlegar (illustrated by a, right). In most interpretations, however, the region also includes: • an area to the east which encompasses the upper drainage basin of the Kootenay River from its rise in the
Rocky Mountains to its passage into the United States at
Newgate. This adds a region spanning from the
Purcell Mountains to the
Alberta border, and includes
Rocky Mountain Trench cities such as
Cranbrook and
Kimberley and the
Elk Valley of the southern
Canadian Rockies, centred on
Fernie. This region also includes part of the
Flathead River drainage basin.
(illustrated by b) • an area to the southwest encompassing the Columbia's drainage from the Kootenay confluence south to the U.S. Border plus the
Salmo River basin. This adds the communities of
Rossland,
Castlegar,
Fruitvale and
Salmo (illustrated by c) Some or all of the following areas to the north, which drain into the Columbia River, are also commonly included in the Kootenays: • The
Arrow Lakes area, which adds
Nakusp.
(illustrated by d) • The Upper Columbia Valley, which parallels the first section of the Kootenay River, including the communities of
Invermere and
Radium Hot Springs (illustrated by e) • The Columbia drainage between the
Kicking Horse Pass and the
Rogers Pass, in and around the town of
Golden.
(illustrated by f) • The Columbia drainage between the
Rogers Pass and the
Eagle Pass, in and around the town of
Revelstoke.
(illustrated by g) When the above regions are added, sometimes the region's name is morphed into
Columbia-Kootenay or
Kootenay-Columbia, although that terminology also includes the Big Bend Country and Kinbasket Lake, to the north of Golden and Revelstoke, which is not generally considered part of the Kootenays, though part of the
Kootenay Land District. Finally, the
Boundary Country, a southern east–west corridor between the
Okanagan and the
Bonanza Pass and drained by the basins of the
Kettle and
Granby Rivers, is sometimes mentioned as being in the West Kootenay, and in other reckonings as being part of the Okanagan. In actuality, the settlement of the Boundary Country predates development in either of the regions it is now attached to, as is also the case with the
Similkameen Country to the west of the Okanagan. In some descriptions, the Boundary Country includes Osoyoos and Oliver in the South Okanagan (rather than the other way around). The Boundary Country is
(illustrated by h) In the event of its inclusion, the Kootenays could be described as the complete Canadian portion of the
Columbia Basin minus lands drained by the
Okanagan River. ==Naming and subdivision==