Schematic view of the clusters and cluster pairs around the Q1410 sightline at different given redshifts (see top label in subpanels). The left-hand panels correspond to the projected in the sky distribution of clusters (circles) and cluster pairs (dashed lines) around the Q1410 sightline (yellow star) in comoving Mpc. Numbers close to the circles correspond to the cluster IDs as given in Table 2. The colour of the circles correspond to the rest-frame velocity difference of each cluster with respect to the given redshift, according to the colour bar scale on the right of the panel. The right-hand panels correspond to portions of the normalized Q1410 HST/COS spectrum within a rest-frame velocity window of ±1000 km s⁻¹ from the given redshift, for the H i Ly α transition (top) and the O vi λλ1032, 1038 Å transitions (middle and bottom, respectively). The spectrum itself is represented by the black lines and the uncertainty is represented by the green line. Our fits to associated absorption line systems are represented by the thick coloured lines according to the colour bar scale on the left of the panel, while the fits for unassociated absorption line systems (i.e. at different redshifts) are represented by the red lines. Absorption line ID and reliability flags are given for associated absorption line systems.