Note 2 — Chapter IV · THE OSTROG AT OMSK
Reading edition
The ostrog was the name given to the stockaded entrenchment or rude fort built by the Cossack invaders of Siberia in the old days. As prisoners were confined more and more in these forts, the word ostrog came to define a place of durance, and is now applied to all local prisons in Siberia, and provincial lock-ups. The prison had disappeared when Kennan looked for it on his visit to Omsk. New buildings have been erected on the site.