For trail runners, a key difference between routes is how “technical” they are. What makes a trail technical? It’s the difference between loping along enjoying nature, and concentrating on precisely where each foot lands and the angle of the placement so that you can continue forward motion as efficiently as possible. Altra designed the Superior 3.5 with technical trails in mind. The cushioning was kept moderate to reduce weight, while the sole provides the traction and precision that technical trails demand.