Two black dots circled lazily. Martian patrol craft, the military on the outlook for any sign of unusual activity. War was almost ready to break out with Terra. Any day, almost any moment.
"We'll be just in time," Erick said. "Tomorrow will be too late. The last ship will have left Mars."
"I hope nothing stops us," Mara said. "I want to get back home when we're through."
Half an hour passed. They neared the City, the wall growing as they walked, rising higher and higher until it seemed to blot out the sky itself. A vast wall, a wall of eternal stone that had felt the wind and sun for centuries. A group of Martian soldiers were standing at the entrance, the single passage-gate hewn into the rock, leading to the City. As each person went through the soldiers examined him, poking his garments, looking into his load.
Erick tensed. The line had slowed almost to a halt. "It'll be our turn, soon," he murmured. "Be prepared."
"Let's hope no Leiters come around," Jan said. "The soldiers aren't so bad."
Mara was staring up at the wall and the towers beyond. Under their feet the ground trembled, vibrating and shaking. She could see tongues of flame rising from the towers, from the deep underground factories and forges of the City. The air was thick and dense with particles of soot. Mara rubbed her mouth, coughing.
"Here they come," Erick said softly.
The merchants had been examined and allowed to pass through the dark gate, the entrance through the wall into the City. They and their silent animals had already disappeared inside. The leader of the group of soldiers was beckoning impatiently to Erick, waving him on.