What is the primary architectural design feature of a panopticon prison?

The primary architectural design feature of a panopticon prison is the circular design that enables observation without prisoners knowing. This concept, introduced by philosopher Jeremy Bentham, is characterized by a centralized watchtower from which a single guard can observe all inmates. The arrangement of the circular structure allows the guard to see every prisoner, who cannot tell whether or not they are being watched at any given moment. This uncertainty creates a psychological effect that encourages inmates to regulate their own behavior, as they assume they could be under surveillance at any time. This design highlights the relationship between power and surveillance, making the panopticon a significant model in discussions of social control and disciplinary mechanisms.

The other choices reflect features that may be present in different types of prison designs, but they do not encapsulate the defining characteristic of the panopticon. For example, complete isolation of prisoners does not align with the panopticon's intent of constant observation and social interaction. Similarly, high walls may prevent escape but are not central to the panopticon’s unique observation principle, and interconnected cells prioritize movement rather than monitoring. Thus, the circular design with its inherent surveillance capability is what distinguishes the panopticon as a revolutionary model in prison architecture.