settlement with restrictions on ingress and egress
Central entry checkpoint to Seversk, a closed city in Russia's Tomsk Oblast, 2010
A closed city or town is a settlement where travel or residency is restricted. In the Soviet Union, closed cities were quarantined for research and military purposes. Many of them have stayed closed in Russia and some post-Soviet states. The concept exists in other countries as well.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).