[2] Relative to other local superclusters, Hercules is considered particularly large, being approximately 330 Mly in diameter.

[4][5] An extremely long filament of galaxies has been found, that connects this group of clusters to the Abell 2197 and Abell 2199 pair.

[5] Abell 2162 in the nearby constellation Corona Borealis is also a member.

[7] In the 1930s, Harlow Shapley studied the structure of the distribution of galaxies in the constellation of Hercules, and was probably first to discover the existence of a supercluster in that region.

In 1976, Massimo Tarenghi suggested that the A2151 cluster was part of a single supercluster, and at a conference in Estonia in 1977, he, together with several other astronomers, presented evidence that it was indeed a supercluster that appeared in that region.