Information recording medium and recording/reproducing apparatus

An information recording medium on which servo patterns, in which recording regions and non-recording regions are disposed corresponding to servo data, are formed in servo pattern regions, comprising:

• a second region where third non-recording regions that are long in a radial direction of the information recording medium are disposed at a predetermined pitch with third recording regions in between in a preamble pattern region provided in each servo pattern region;
• and
• a fourth non-recording region that connects the third non-recording regions that are adjacent in a direction of rotation of the information recording medium, the fourth non-recording region being provided in the second region,
• wherein a fourth recording region is provided at a position that is adjacent in the direction of rotation to the second region and where a read of the servo data is carried out following the second region, and
• a length in the direction of rotation of the fourth recording region is longer than a length in the direction of rotation of the third recording regions at corresponding same-pattern-radius positions.