Deep enough to swallow skyscrapers and filled with deadly toxic gases, it plunges so far into Earth even robots have never reached the bottom
Hidden at the bottom of a rocky ravine in the Hůrka u Hranic National Nature Reserve in eastern Czech Republic is a small lake of murky green water that can be spotted from a viewing platform above. At first glance, this might appear fairly unremarkable, but what lies below the surface is the Hranice Abyss…
