From the marker:
A colourful steamboat era preceded the railways. During mining boom days of 1893-98 a fleet of sternwheelers ran north from the railway at Jennings, Mont., to Ft. Steele and vicinity.
Carrying prospectors, freight, and ore they battled treacherous currents, shoals, and canyons to provide a vital transport link. The Kootenays owe them much!