In the US, we like everything big, including our traffic lanes. The narrow lanes here are one of my biggest worries with driving in Switzerland and the rest of Europe. In the US, curbs are made of poured concrete.
The edge of the road there looks kind of like this. Here, they are tire poppers. They are made of individual pieces of stone (granite?) that are a few feet long.
No matter how narrow the road, do not touch them with your tires!