Finding the hotsprings:
From Nakusp, take Highway 23 north about 14 mi/23 km up the east side of Upper Arrow Lake.  Turn right 1.5 mi/2.4 km past a rest area onto St. Leon Forest Road (south of the bridge over St. Leon Creek) and climb 2 mi/3.2 km.  St Leon isn't marked on the forest map.

The hot springs:
A clearing in the forest reveals a concrete pool with free-flowing curves and a smoothly sloped bottom.  The kidney-shaped pool, built by a highway crew, is a good 15 ft/4.6 m long and 2.5 ft/.8 m deep in the center.  The springs emerge from fractures in nearby rocks and are piped into the pool to provide a blissful soak at around 103 degrees F/ 39 degrees C.  There's also a small pool in the rocks above.
St. Leon Hot Springs is on private property but open to the public.  A hotel dating back to gold rush days once stood nearby, as at nearby Halcyon, but both hotels burned down in the 1950s and no trace remains today.  The forest is magnificent and the gourmet sampler of wild dips would be hard press to improve on the present user-built pool.