Ostrov

Ostrov takes its name from the island in the Velikaya River on which its fortress stood. An outpost on the southern frontier of the Pskov Republic, it first appears in a chronicle in 1341, when its men came to the aid of Pskov against the Livonians. The stone fortress on the island, protected by towers and a defensive passage, formed a formidable part of Pskov's border defenses. Within it stood the stone Church of Saint Nicholas, built in 1542.

The Livonian Order captured and devastated Ostrov in 1501, using artillery and fire arrows against the fortress. During the Livonian War, Stephen Báthory's forces took it after a fierce assault in 1581; the Peace of Jam Zapolski returned it to Russia the following year. The town's defensive importance declined after the Great Northern War, and it became an uyezd center. Merchants dealing in flax, together with leather and bristle trades, contributed to its later growth.