Peter Riedel could hardly have chosen a better location to ply his trade. We've seen rock balancers in the eastern beaches, in the western beaches, and even at the Ex, but this is the first time we've seen one working the Humber River. Literally in the river.

The Humber cascades over a low waterfall in Étienne Brûlé Park before bubbling just a few centimetres deep across a short stretch of river rock. The only sounds here come from the rushing river and picnicking families. Visitors to the park on a busy Sunday afternoon include cyclists, walkers, joggers, and skaters. And then there's the guy crouched in the middle of the river, surrounded by some fifty rock towers of every imaginable description.

Riedel, who has been balancing rocks on the Sunnyside Beach seawall for three seasons, recently moved up the Humber to take advantage of the idyllic setting, the abundant raw material and the type of permanence the river lends to his work. At Sunnyside, his towers would "inevitably get knocked down, pushed down, or toppled." It's hard to imagine anyone accidentally bumping into a rock tower in the middle of a river. The towers won't last a lifetime, but will almost certainly stand until a big storm or very determined malcontent knocks them down.

What drives someone to balance rocks? We imagine that it's a great way to relieve stress. It requires such concentration that you can't help but forget whatever else may be bothering you. We may have to take it up one day. For those who don't want to get their hands dirty (or feet wet), there's even a home version.

Photos by Val Dodge.