Danilovka was one of the last unexpectedly big river tunnels that we have discovered. It has an underwater portal into the Moscow river, is not much mentioned anywhere and can’t be evidently traced from the surface.
It is the first drain built in Moscow after the revolution. The approximate year of construction is 1928. The diameter of the large part is around 2.5 m. The floor was covered in brick to prevent the concrete from degrading.
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