Roughlock gets its name from the wagon days. Freight drivers coming down steep Black Hills grades would jam a roughlock, a kind of drag shoe, under a wheel to stop it turning, and the name stuck to a creek that lots of those wagons must have crossed. What I can say is that the falls are good: Little Spearfish Creek drops over a wide limestone lip into a pool, and the whole thing is framed by evergreens and the sort of damp rock that smells faintly of minerals.
From the road you reach it by a short side lane up toward the nature centre, then a gentle walk down to a viewing platform. It is a more serious waterfall than Bridal Veil, and in spring runoff it throws up a roar and a fine mist. Late summer can see it reduced to a modest pour. Autumn, when the aspens go butter-yellow, is the postcard season, and it also brings the heaviest traffic, so aim for an early start.
The Spearfish Canyon Scenic Byway itself is about twenty miles of mellow riding, and this is its high-water mark for me. The curves are gentle and flowing, the surface is usually kind, and the canyon walls make the thing feel enclosed in a way open prairie roads never do. The temperature can swing sharply: you may leave Spearfish in shirtsleeves and want a liner by the time you reach the upper canyon. Rain squalls tend to arrive quickly from the west. Watch for tourists in rental cars stopping without warning, and for deer at dusk.
The Black Hills around here were taken from the Lakota after gold was found in 1874, a history that remains painful and legally unresolved, and the Hills are sacred to the Lakota people. That is worth keeping in mind as you ride through pine-scented country that looks like an easy holiday backdrop.
Fuel is not available at the falls. Spearfish, about seventeen kilometres north, has plenty, and Lead and Deadwood are close at the southern end. If you want a sit-down meal after the walk, either end of the canyon is a better bet than hoping something will turn up in between.