Representation of the position of the Q1410 sightline with respect to different independent cluster pairs in our sample. The y-axes correspond to the impact parameter to a given cluster pair, Δd, while the x-axes correspond to the distance to the closest galaxy cluster in a given cluster pair, along the cluster-pair axis, Δx, (see Fig. 1 for a schematic diagram). The four panels correspond to different absorption line samples, from top to bottom: total H i, narrow H i (NLAs; b < 50 km s⁻¹), broad H i (BLAs; b ≥ 50 km s⁻¹), and total O vi. Filled symbols correspond to portions of the sightline showing absorption lines within Δv = 1000 km s⁻¹ from the redshifts of a given cluster pair, where the sizes of the symbols are proportional to the number of absorption lines. Empty symbols correspond to portions of the sightline showing no absorption. When multiple cluster pairs lie at similar redshifts (i.e. from grouped ones), the absorption lines are associated with the one having the smallest impact parameter value and the rest of the cluster pairs are obviated. We also show the typical virial radii of our sample of clusters with a quarter dashed circumference of radii 1 Mpc centred at the origin. See Section 7.1 for further details.