Honeycomb structure

A honeycomb structure comprising:

• a ceramic block including at least one honeycomb fired body that has a first peripheral wall constituting a periphery of the at least one honeycomb fired body and that has cell walls extending along a longitudinal direction of the at least one honeycomb fired body to define cells comprising:
• peripheral cells in contact with the first peripheral wall of the at least one honeycomb fired body constituting a periphery of the ceramic block;
• basic cells arranged at an inner side of the peripheral cells;
• and
• the peripheral cells including deformed cells each having a different shape from the basic cells in a cross section perpendicular to the longitudinal direction of the at least one honeycomb fired body, each of the deformed cells being capable of receiving therein a circle of about 0.9 mm in diameter in the cross section perpendicular to the longitudinal direction.