  This thesis is dedicated to the study of open spin networks. We formulate
quasi-local descriptions of loop quantum gravity. We investigate the
coarse-graining procedure via tracing over bulk degrees of freedom, which
encodes all that we can know about the quantum state of geometry from probing
the boundary. We prove a boundary-to bulk universal reconstruction procedure,
to be understood as a purification of the mixed boundary state into a pure bulk
state. We then move to define multipartite entanglement in spin networks, and
show the computation of entanglement excitation from holonomy operator, which
also allows us to glimpse bulk curvature from entanglement. Moreover, by
investigating another coarse-graining procedure - via gauge-fixing, which does
not trace over any bulk degrees of freedom, we show a new interesting
connection between bulk geometry and boundary observables via the dynamics of
entanglement. Finally, we define the spin network entanglement between spin
sub-networks, which correspond to spatial sub-regions. We then generalize the
coarse-graining approach, and prove that the entanglement between spin
sub-networks is preserved under the coarse-graining (via gauge-fixing).
