Cathedral for the Salvation of Romanian People

The People's Salvation Cathedral, also known as the National Cathedral, is an Eastern Orthodox cathedral under construction in Bucharest to serve as the patriarchal cathedral of the Romanian Orthodox Church. It is located in central Bucharest on Spirea's Hill, facing the same courtyard as the Palace of Parliament which is the heaviest building in the world, the cathedral having a one-tenth of its weight and about one-fifth of its volume. Situated behind the Palace of Parliament, this will make it 50 metres taller than the Palace, and will help to make the cathedral an iconic landmark in the city. The People's Salvation Cathedral to 135 metres height, holds a dominant position in Bucharest's cityscape, being visible from all approaches to the city.

It is the tallest and largest Eastern Orthodox church building by volume, and area, in the world.

Source: Wikipedia