Superclusters!
Our own galaxy and its Local Group belong to a supercluster called the Local Supercluster. It similar in shape to a flattened ellipse (pancake), with the Virgo Cluster near its center and the Local Group near one end; its extent in the longest direction is about 40-50 Mpc. The large concentration of galaxies on the left side of the following diagram represents part of the Local Supercluster.
Supercluster:
1) Superclusters are large groups of smaller galaxy groups and clusters, as well as isolated galaxies.
2) They are very large structures spanning between 20 and 100 Mpc or more in their long dimension.
3) They were once thought to be the largest structures in the Universe, but are now seen as components of truly vast walls and filaments.
4) Astronomers believe that there are some 10 million superclusters in the observable Universe.
5) Usually contain a lot of dark matter
6) They have an estimated 10^15 solar mass
7) The Virgo Supercluster fills a volume of space 110 million light-years and contains at least 100 galaxy groups and clusters.
8) The latest information from deep space telescopes suggest these fundamental structures exist in a honeycomb or bubble-like formation
9) The observations astronomers give us, may insight into the early conditions of the Universe.
10) The density of galaxies in the Virgo Cluster is about ten times greater than that in the Local Group.