the Laniakea Supercluster: a supercondensation of galaxies in the local Universe, containing a about 1e17 solar masses (!) in total, and stretching for the impressive length of 160Mpc from side to side https://en.wikipedia.org/wiki/Laniakea_Supercluster
Luckily you have one of the discoverers active on this platform: @pomarede
mmatessa