Martin shrugged. "Clear around the city? I'd like to know what it
is--was--for."
"Defense," Rodney, several yards behind, suggested.
"Could be," Martin said. "Let's go in."
The three crossed the metal band and walked abreast down a street,
their broad soft soled boots making no sound on the dull metal. They
passed doors and arches and windows and separate buildings. They moved
cautiously across five intersections. And they stood in a square
surrounded by the tallest buildings in the city.