The Laniakea Supercluster is home to the Milky Way and approximately 100,000 other nearby galaxies!
Superclusters are some of the universe's largest structures and have boundaries that are difficult to define, especially from the inside.
Within a given supercluster, most galaxy motions will be directed inward, toward the center of mass. In the case of Laniakea, this gravitational focal point is called the Great Attractor, and influences the motions of the Local Group of galaxies, where the Milky Way galaxy resides, and all others throughout the supercluster.
Unlike its constituent clusters, Laniakea is not gravitationally bound and is projected to be torn apart by dark energy.
The Great Attractor was a gravitational anomaly, as an immense mass seemed to pull on the Milky Way.