human
Generate a description of a suspenseful scene inside a tunnel cavern with granite, ceiling, and the tunnel.
assistant
The tunnel branches at this point, but the water all flows northwest. To the south the tunnel abruptly ends at a pile of broken granite. The collapse of the ceiling has totally sealed off travel in that direction and plugged the water's flow. The sound of rushing water echoes down the tunnel from the northwest, and the water's flow picks up speed as it moves northwestward. The northwestern tunnel also appears to be more brightly lit than the tunnel here or in the other directions.