Redsand Canyon And the highway signs say we're close

The imperator continued forward into the caves, and Kallik followed closely behind. The deeper inside they moved, the less he could rely on his sight. Eventually, they were in complete darkness and at the mercy of their hearing and smell only. The first time he had wandered into the darkness, it had been alarming; he had promptly made his way back out. But now, he knew what to expect, and he tuned into his remaining senses. 

He stopped when Germanicus did and then followed him up onto the wall as the imperator spoke to him. When the auxillary stopped, he drew in a deep breath. Water, he said first. And the fox we've been following. It had definitely come this way. He wondered if the creature used these caves to travel unseen through parts of the mountain.