Abstract: A method of excavating a tunnel in bedrock, including the steps of boring an outer peripheral slot in the bedrock, boring a plurality of horizontal slots in a bedrock section surrounded by the outer peripheral slot such that the bedrock section is divided into a plurality of bedrock portions by the horizontal slots, boring a plurality of vertical slots in one of the bedrock portions such that the one of the bedrock portions is divided into a plurality of bedrock blocks by the vertical slots, removing the bedrock blocks from the bedrock so as to define a working space, and providing an excavator in the working space such that the remaining ones of the bedrock portions are sequentially excavated by the excavator.