  We experimentally demonstrate the photonic realization of a dispersionless
flat-band in a quasi-one-dimensional photonic lattice fabricated by ultrafast
laser inscription. In the nearest neighbor tight binding approximation, the
lattice supports two dispersive and a non-dispersive (flat) band. We
experimentally excite superpositions of flat-band eigen modes at the input of
the photonic lattice and show the diffractionless propagation of the input
states due to their infinite effective mass. In the future, the use of photonic
rhombic lattices, together with the successful implementation of a synthetic
gauge field, will enable the observation of Aharonov-Bohm photonic caging.
