  The cosmic web consists of a nested hierarchy of structures: voids, walls,
filaments, and clusters. These structures interconnect and can encompass one
another, collectively shaping an intricate network. Here we introduce the
Hierarchical Spine (H-Spine) method, a framework designed to hierarchically
identify and characterize voids, walls, and filaments. Inspired by the
geometrical and dynamical constraints imposed by anisotropic gravitational
collapse, the H-Spine method captures the geometry and interconnectivity
between cosmic structures as well as their nesting relations, offering a more
complete description of the cosmic web compared to single-scale or multi-scale
approaches.
  To illustrate the method's utility, we present the distribution of densities
and sizes of voids, walls and filaments identified in a 3-level hierarchical
space. This analysis demonstrates how each level within the hierarchy unveils
distinctive densities and scales inherent to cosmic web elements.
