A north-referenceable goniometer for azimuthal orientation determination of a sighting device has a base, a rotary part, a rotation angle encoder for determining a rotational position of the rotary part about an upright axis, a gyroscope fixed on the rotary part and having a measuring device oriented orthogonally to the upright axis for determining a component of the Earth rotation vector, and an evaluation unit for determining the azimuthal angle of the geographical north pole. The goniometer also includes an acceleration sensor, and the evaluation unit is formed such that, using the evaluation unit, the determined component of the Earth rotation vector is corrected by a sink rate of the goniometer, determined with the aid of the acceleration sensor, and a systematic measurement error of the gyroscope is corrected by determining measurement values of the component of the Earth rotation vector in at least three different rotational positions.