A direction calculation apparatus configured to calculate a direction to be presented to a guided person using a force sensation presentation device gripped by the guided person, the direction calculation apparatus characterized by comprising: a first matrix acquisition unit configured to, using a geomagnetic map including a geomagnetic vector of a reference posture of the force sensation presentation device in a reference coordinate system at a position included in a predetermined range and a gravitational acceleration vector of the reference posture of the force sensation presentation device in the reference coordinate system at the position included in the predetermined range, acquire a first matrix composed of a geomagnetic vector of the reference posture of the force sensation presentation device in the reference coordinate system at the current position, a gravitational acceleration vector of the reference posture of the force sensation presentation device in the reference coordinate system at the current position, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector from a current position of the force sensation presentation device, wherein said geomagnetic map is recorded in a recording unit of the direction calculation apparatus; a second matrix acquisition unit configured to acquire a second matrix composed of a geomagnetic vector of a current posture of the force sensation presentation device in the reference coordinate system at the current position, a gravitational acceleration vector of the current posture of the force sensation presentation device in the reference coordinate system at the current position, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector; and a presented direction calculation unit configured to use the first matrix and the second matrix to calculate, from a first instructed force sensation vector in a reference coordinate system indicating a direction to be instructed to the force sensation presentation device, a second instructed force sensation vector in a force sensation presentation device coordinate system indicating a direction to be instructed to the force sensation presentation device as the direction to be presented to the guide person. a first matrix acquisition unit configured to, using a geomagnetic map including a geomagnetic vector of a reference posture of the force sensation presentation device in a reference coordinate system at a position included in a predetermined range and a gravitational acceleration vector of the reference posture of the force sensation presentation device in the reference coordinate system at the position included in the predetermined range, acquire a first matrix composed of a geomagnetic vector of the reference posture of the force sensation presentation device in the reference coordinate system at the current position, a gravitational acceleration vector of the reference posture of the force sensation presentation device in the reference coordinate system at the current position, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector from a current position of the force sensation presentation device, wherein said geomagnetic map is recorded in a recording unit of the direction calculation apparatus; a second matrix acquisition unit configured to acquire a second matrix composed of a geomagnetic vector of a current posture of the force sensation presentation device in the reference coordinate system at the current position, a gravitational acceleration vector of the current posture of the force sensation presentation device in the reference coordinate system at the current position, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector; and a presented direction calculation unit configured to use the first matrix and the second matrix to calculate, from a first instructed force sensation vector in a reference coordinate system indicating a direction to be instructed to the force sensation presentation device, a second instructed force sensation vector in a force sensation presentation device coordinate system indicating a direction to be instructed to the force sensation presentation device as the direction to be presented to the guide person.