Question: has anyone dug to the center of the earth?
Answer: Humans have drilled over 12 kilometers (7.67 miles) in the Sakhalin-I. In terms of depth below the surface, the Kola Superdeep Borehole SG-3 retains the world record at 12,262 metres (40,230 ft) in 1989 and still is the deepest artificial point on Earth.