human
Write a detailed description of a foreboding dock scene with an iron portcullis, tunnel, and footbridge.
assistant
Copper Avenue comes to an abrupt end as it approaches the mountain. The sound of the water almost drowns out the shouts of the dockworkers to the north. A small footbridge leads across the water into a large tunnel in the side of the mountain. The mouth of the tunnel is open, but the spires of an iron portcullis peek down from the top, able to barricade the tunnel if necessary.