Riding Gravel roads would fit into pretty much any of the cycling forums, and no, there isn't going to be a new subforum for it. You can ride a mountain bike on gravel, a Cyclocross, a beach cruiser, or even a razor tired road bike if you feel a bit crazy.
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. “He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you.”- Fredrick Nietzsche
"We can judge the heart of a man by his treatment of animals." - Immanuel Kant