People swim across Lake Ontario from Niagara on the Lake to Toronto–a distance of 52 km (32.3 miles). The lake is fresh water, so this swim is considered more difficult than ocean swims of similar length because salt water provides more boyancy than fresh water. (For comparison, the English Channel is 21 miles across and, despite strong currents, generally takes less time to cross.) Is one direction (south to north or north to south) more difficult?