The Tunguska disaster, as one of the most mysterious phenomena of the 20th century, is not an abstract phenomenon but has a rich factual material base. Kulik, the first to research this disaster, said that since the event had take place on the territory of Russia it was necessary to record all traces of this phenomenon. Confronting our History, we had to study it. In this book the facts presented are the fruit of various scientific investigations, as well as of numerous eyewitness accounts. The Tunguska cosmic body put its signature on recorders, which were working at the time of the disaster and created a unique “autograph” both of seismic and air waves, and also of the geomagnetic disturbance. Each chapter in this book is, in some way, an element of a mosaic which should find its place in the whole puzzle. But it has been determined that most elements of the puzzle contained abnormal features typical of such unprecedented phenomenon as the Tunguska disaster.