The disclosed technology is directed to a bendable tube bendable by a bending wire that comprises a plurality of bending pieces configured to be joined together. The bending pieces including a distal-end bending piece disposed at a foremost end of the bendable tube. The distal-end bending piece includes a flat portion forming a flat surface. An attaching portion is disposed on the flat portion. The attaching portion having a first insertion region and a second insertion region. The bending wire is inserted from within the distal-end bending piece outwardly of the distal-end bending piece through the first insertion region. The bending wire is inserted from outside the distal-end bending piece into the distal-end bending piece through the second insertion region. The bending wire disposed outside the distal-end bending piece between the first insertion region and the second insertion region being attached to the distal-end bending piece by the attaching portion.