Heated Sidewalks in Reykjavik

I saw a documentary about Reykjavik where they pump geothermal hot water under the sidewalks to melt ice and snow. The simplicity of solution has been stuck in my head since. Iceland sits on volcanic activity that produces practically free hot water. Instead of salting roads or plowing constantly they just route the heat underground through pipes, so the sidewalks stay clear all winter without any chemicals or labor. I want every cold city to have this, though I know the geothermal part is specific to Iceland's geology. The principle of using waste heat from the ground to solve a surface problem feels transferable. Infrastructure cost is high upfront but operating cost is near zero because the heat is already there. Over decades the math works out better than annual plowing budgets. It also means fewer slip-and-fall injuries for elderly people, fewer car accidents on icy intersections, and less salt runoff poisoning the soil and groundwater. Campus here gets so icy in January that they close walkways, and I keep thinking about how different that would be if the ground just stayed warm. Heated sidewalks in Reykjavik don't look any different from normal concrete — you wouldn't know unless you noticed the steam rising or the absence of ice. Best infrastructure usually is invisible, and this is a good example.