From left to right: a) VISTA-NIR image of the ISF (Meingast et al. 2016); b) IRAM 30 m integrated N₂H⁺ (1−0) emission; c) N₂H⁺ line velocity centroid (V_LSR) and d) N₂H⁺ Full-Width-Half-Maximum (FWHM) as a function of declination. Map offsets are referred, in radio projection, to the position of the Orion BN source (white cross). N₂H⁺ contours are equally spaced every 2 K km s^-1. For reference, the first N₂H⁺ contour is superposed to the IR image. The location of the most prominent molecular fingers (e.g., the OMC-1 ridge, MF3, and HVF; Rodriguez-Franco et al. 1992) are indicated by red lines in the integrated intensity map. The magnitude of representative gradients with 1 (green) plus 5, and 7 (blue) km s^-1 pc^-1 are indicated in the velocity plot. The position of the OMC-1 South clump with the most blue-shifted velocity is indicated in both maps (green cross) and kinematic plots (green dashed line).