Matochkin Strait

Matochkin Strait or Matochkin Shar () is a strait, structurally a fjord, between the Severny and Yuzhny Islands of Novaya Zemlya. It connects the Barents Sea and the Kara Sea.
Geography.
The Matochkin Strait is one of the largest fjords in the world.
The banks along the strait are high and steep. Its length is approximately and its width in its narrowest part is approximately
. The strait is covered with ice for the most of the year. There are fishing settlements along the strait (Matochkin Shar, Stolbovoy).
History.
The Tsar Bomba was detonated in the vicinity of Matochkin Strait in 1961, just north of neighboring Mityushikha Bay.
It is also the site where, from 1963 to 1990, about 39 underground nuclear tests took place in a vast array of tunnels and shafts under Mount Lazarev and other massifs. After 2000, Russia started to reactivate the test site by enlarging old tunnels and starting construction work. Each summer since then various subcritical hydronuclear experiments have taken place. In 2004, Rosatom reportedly performed a series of subcritical hydronuclear experiments with up to of weapon-grade plutonium each.