Illustration of the location of identified H.E.S.S. sources in the Galaxy with respect to HGPS completeness (sensitivity limits). This is a face-on view; the spiral arms (Vallée 2014) are schematically drawn as gray bars. The HGPS horizons for source luminosities of 10³³ and 10³⁴ erg s⁻¹ (for a putative 5σ detection of a point-like source, same as Fig. 4) are depicted by light blue and light brown lines (and shaded regions therein), respectively. The source distances are from SNRcat (Ferrand & Safi-Harb 2012) and ATNF pulsar catalog (Manchester et al. 2005). When no distance uncertainties were available, we applied a generic uncertainty of factor two on the distance. The three labeled sources are the Galactic γ-ray sources outside the HGPS region detected by H.E.S.S.