Cities located on the planet Poderis were defended by Shield-Barriers, which were enormous, angled walls. These structures served to protect the cities from seasonal winds that reached speeds of 200 kilometers per hour. Reaching approximately 100 meters tall, the walls were incredibly smooth, lacking any windows, doors, or other apertures. The smooth surface and sharply inclined angle prevented climbing without specialized gear. Their design focused on diverting the winds above the city, rather than halting them entirely. This angled construction contributed to the barriers' extended lifespan.
In the year 9 ABY, Luke Skywalker found himself cornered on a rooftop connected to a shield-barrier on Poderis, attempting to evade capture. His mission involved discovering if Poderis served as a transit hub for the Empire's emerging clone operations. Employing his enhanced sensory skills, Luke scanned for nearby Imperials. He perceived areas where his abilities were ineffective, indicating the presence of ysalamiri. Realizing he was ensnared in a trap, he leapt onto the roof, only to discover his escape routes were blocked.
From a torn fragment of his tunic's left sleeve, he created a protective covering for his hand. Subsequently, he carved a channel into the wall's exterior, into which he inserted his hand, and began to descend. He used his lightsaber to carve a slanted path for his hand to follow. After traversing roughly 100 meters across the wall's surface, he created a breach in the shield-barrier, re-entering the city.