World's Biggest Holes

After almost three months of round-the-clock drilling, geologists have finished a 1.1-mile borehole to the bottom of the United States' largest impact crater, a 53-mile-wide depression at the mouth of the Chesapeake Bay. They have retrieved rocks and sediments documenting the moment of impact about 35 million years ago, the cataclysmic tsunamis that followed, and the recovery of life in the region. This project follows in the grand tradition of boring into the earth in search of answers.