  Lattice Gauge Theories form a very successful framework for studying
nonperturbative gauge field physics, in particular in Quantum Chromodynamics.
Recently, their quantum simulation on atomic and solid-state platforms has been
discussed, aiming at overcoming some of the difficulties still faced by the
conventional approaches (such as the sign problem and real time evolution).
While the actual implementations of a lattice gauge theory on a quantum
simulator may differ in terms of the simulating system and its properties, they
are all directed at studying similar physical phenomena, requiring the
measurement of nonlocal observables, due to the local symmetry of gauge
theories. In this work, general schemes for measuring such nonlocal observables
(Wilson loops and mesonic string operators) in general lattice gauge theory
quantum simulators that are based merely on local operations are proposed.
