After passing stone towers and crossing districts, they reached the end of the city and found a sheer stone wall standing there.
Philip was somewhat surprised. He could not tell whether the city had originally been built right against the wall, or whether a mountain had been half-enclosed before construction and then carved into this shape.
What surprised him even more was the enormous arched opening in the wall, black as pitch, with no telling where it led. Dense U-shaped metal pipes extended from the opening and lay across the ground, though he had no idea what they were for.
Later, he heard someone explain that those U-shaped metal pipes were called tracks, while the round opening was called a tunnel.
Philip, his son, and the others were herded by the officer named Norton Wanwa onto a dam-like raised platform beside the tunnel and told to wait quietly.
After waiting for around ten minutes, everyone suddenly turned to look into the tunnel at once, having heard a strange sound coming from within.
"Clack, clack..."
The ground around them trembled slightly, as though some terrifying beast were about to charge out of the tunnel, and the crowd could not help growing restless.
"Clack-clack-clack..."
The sound from the tunnel grew louder and louder, harshly tormenting everyone's eardrums, while white steam spread outward.
The unrest in the crowd worsened, and fear began to take hold.
"Clack-clack-clack! Whooo!"
At last, the sound suddenly turned into a shrill, drawn-out whistle that pierced everyone's ears like an awl. They instinctively raised their hands to cover their ears. Then, through wide eyes, they saw a steel monster burst through the thick white steam and come roaring out of the tunnel.
The steel monster had an incredibly long body, several hundred meters in length, divided into section after