Kosoy Kaponir, Kiev

The Kosoy Kaponir is a striking piece of hidden history nestled within the capital's Pechersk district, part of the larger Kyiv Fortress complex.

Constructed in 1844–1846 as a defensive fortification (specifically the “oblique caponier” of the Hospital Bastion) it was built at an angle to the main earthworks to allow flanking artillery fire—hence the name “kosoy” which means “oblique.”

Though originally designed for military defence—housing thick brick and stone walls with embrasures and loopholes for cannon and rifle fire—the Kosoy Kaponir’s role soon shifted. By the 1860s it had been converted into a maximum‑security prison for political inmates, including participants of the Polish Uprising of 1863 and revolutionaries from 1905–1907. It gained the grim nickname “Kyiv Shlisselburg” in reference to the infamous Russian prison.

Today, the Kosoy Kaponir offers visitors a compelling experience of the capital's lesser‑known past. You can explore well‑preserved ramparts, earthen embankments, and underground corridors that once held weapons—and later, prisoners.

A museum now occupies part of the site, with displays of prison uniforms, personal belongings of inmates, and the infamous death‑row carriage. Ideal for history enthusiasts, especially those curious about military architecture and the darker chapters of Ukrainian history.