As Fig. 9, focusing on the region around the southeast “filament” described in Sect. 3.2.3 and marked by the gray box. The contours are the H I intensity integrated over the velocity range − 46 to − 40 km s⁻¹ and were selected to highlight the H I filament present in this region; the levels are 3, 6, 9, and 12 K km s⁻¹ transitioning from white to dark gray. The smooth gradient in the Faraday depth is located below the edge of the H I filament, while inside the filament the Faraday depth behavior is more complex. Leakage from the bright source 3C295 dominate the top of the image. The three crosses mark the locations of the spectra shown in Fig. 12.