Examples of supercluster systems detected in eRASS1. Upper panels: the most distant supercluster system identified in eRASS1: 1eRASS-SC J0530-4138, a cluster pair at redshift 0.802. The red crosses mark the position of the two member clusters: 1eRASS J052957.4-413822 at z = 0.811 ± 0.007 and 1eRASS J053040.8-413904 at z = 0.793 ± 0.012. Lower panels: a rich supercluster 1eRASS-SC J0529-2226 detected at redshift 0.17, with the four member clusters marked as red crosses. The left panels show the eROSITA X-ray exposure-corrected images in the 0.2–2.3 keV band, after smoothing with a Gaussian of σ = 12″. The right panels show the optical images from the Legacy Survey, with the X-ray emission overlaid as white contours.