The authors report the production of a matter-wave bright soliton in an ultra-cold $^7$Li gas. By tuning the effective interaction between atoms in a Bose-Einstein condensate (BEC) using a Feshbach resonance, they create an attractive interaction that stabilizes the condensate. The soliton is then released into a one-dimensional optical waveguide, where it propagates without dispersion over a macroscopic distance of 1.1 mm. A theoretical model explains the stability region of the soliton, which is crucial for future applications in coherent atom optics, atom interferometry, and atom transport. The experimental setup involves cooling and transferring atoms from a magnetic trap to an optical dipole trap, followed by tuning the scattering length and deforming the trapping geometry to form the soliton. The soliton's stability is confirmed through measurements of its wave-packet size and theoretical analysis of the Gross-Pitaevskii energy functional.The authors report the production of a matter-wave bright soliton in an ultra-cold $^7$Li gas. By tuning the effective interaction between atoms in a Bose-Einstein condensate (BEC) using a Feshbach resonance, they create an attractive interaction that stabilizes the condensate. The soliton is then released into a one-dimensional optical waveguide, where it propagates without dispersion over a macroscopic distance of 1.1 mm. A theoretical model explains the stability region of the soliton, which is crucial for future applications in coherent atom optics, atom interferometry, and atom transport. The experimental setup involves cooling and transferring atoms from a magnetic trap to an optical dipole trap, followed by tuning the scattering length and deforming the trapping geometry to form the soliton. The soliton's stability is confirmed through measurements of its wave-packet size and theoretical analysis of the Gross-Pitaevskii energy functional.