human
Write a detailed description of a mysterious scene inside a tunnel cavern with a trickle of water.
assistant
This section of the tunnels is almost perfectly elliptical and leads generally in an east-west direction. It seems to have been formed by rapidly moving water eons ago, but now it is almost dry as time and use have forced the water table down deeper. A small trickle of clear water still travels along the center of the tunnel eastward.