Novaya Zemlya largest number of fjords in the Russian Federation. Novaya Zemlya separates the Barents Sea from the Kara Sea. The total area is about . The highest mountain is located on the Northern island and is 1,547 meters (5,075 ft) high. Compared to other regions that were under large ice sheets during the last glacial period, Novaya Zemlya shows relatively little isostatic rebound. Possibly this is indebted to a counter-effect created by the growth of glaciers during the last few thousand years. The ecology of Novaya Zemlya is influenced by its severe climate, but the region nevertheless supports a diversity of
Novaya Zemlya avalanche that blocked two glacial streams and created a lake in length. Over its history as a nuclear test site, Novaya Zemlya hosted 224 nuclear detonations with a total explosive energy equivalent to 265 megatons of TNT. For comparison, all explosives used in World War II, including the detonations of two US nuclear bombs, amounted to only two megatons. In 1988–1989, "glasnost" helped make the Novaya Zemlya testing activities public knowledge, and in 1990 Greenpeace activists staged a protest at the site. The last nuclear test explosion was in 1990 (also the last for the entire Soviet Union and Russia).