Prydonian Wall

The Prydonian Wall was a tall basalt structure separating Prydos from Riff City. Its defensive technologies included guard tunnels, sound shingles, and laser surveillance towers. (PROSE: Gallifrey: A Rough Guide)

Behind the scenes

 * The Prydonian Wall originated in Dave Martin's Find Your Fate novel The Garden of Evil, which explained that it was built to keep students focused on their studies. Similar walls surrounded Patrexi and Arcalia.