Don't forget "crushed stone". It's not the same as packed dirt. The fine textured, sharp edged bits interlock, and can be very solid and fast riding. It's sand sized particles, but not at all like riding on sand. The GAP trail, for instance, is built from this.
I was impressed by the smooth graded gravel roads in the NY Catskills, too. Much nicer than the midwest chunky gravel.
Last edited by rm -rf; 03-29-21 at 10:37 AM.