A matter-wave bright soliton was produced in an ultra-cold $^{7}$Li gas. The effective interaction between atoms in a Bose-Einstein condensate (BEC) was tuned using a Feshbach resonance from repulsive to attractive. The soliton was observed to propagate without dispersion over 1.1 mm in a one-dimensional optical waveguide. A theoretical model explained the soliton's stability. These solitons have potential applications in coherent atom optics, atom interferometry, and atom transport. Solitons are localized waves that travel long distances without changing shape or attenuating. They have been studied in various fields, including physics and nonlinear optics. In this study, a BEC of $^{7}$Li atoms was used as a macroscopic matter-wave to form a soliton. Nonlinearity was provided by binary atomic interactions, leading to a mean-field potential. For negative scattering lengths, the effective interaction is attractive, and a trapped BEC is stable only for a number of atoms below a critical value. The soliton was produced from a $^{7}$Li BEC in the internal atomic state $|F=1, m_F=1\rangle$. A Feshbach resonance allowed tuning of the scattering length from positive to negative values using a magnetic field. The atoms were cooled and transferred into an optical dipole trap. The scattering length was tuned to a negative value to enable soliton formation. The trapping geometry was deformed adiabatically to a cylindrical geometry, and the vertical trapping beam was switched off to release the BEC into the horizontal waveguide. The soliton was observed to propagate without dispersion over 1.1 mm. The soliton's width remained constant, indicating no dispersion. The soliton's stability was analyzed using a three-dimensional Gross-Pitaevskii energy functional. The results showed that the soliton exists within a narrow window of the parameter $Na/a_{\perp}^{ho}$. The number of atoms allowing soliton formation was found to be between $4.2 \times 10^3$ and $5.2 \times 10^3$, in agreement with the measured number of $6(2) \times 10^3$ atoms. The soliton's size was found to be $l_z \simeq 1.7 \mu m$, below the imaging resolution limit. The study also showed that the soliton's stability could be extended by removing the expulsive axial potential. Future work includes studying soliton coherence and binary collisions.A matter-wave bright soliton was produced in an ultra-cold $^{7}$Li gas. The effective interaction between atoms in a Bose-Einstein condensate (BEC) was tuned using a Feshbach resonance from repulsive to attractive. The soliton was observed to propagate without dispersion over 1.1 mm in a one-dimensional optical waveguide. A theoretical model explained the soliton's stability. These solitons have potential applications in coherent atom optics, atom interferometry, and atom transport. Solitons are localized waves that travel long distances without changing shape or attenuating. They have been studied in various fields, including physics and nonlinear optics. In this study, a BEC of $^{7}$Li atoms was used as a macroscopic matter-wave to form a soliton. Nonlinearity was provided by binary atomic interactions, leading to a mean-field potential. For negative scattering lengths, the effective interaction is attractive, and a trapped BEC is stable only for a number of atoms below a critical value. The soliton was produced from a $^{7}$Li BEC in the internal atomic state $|F=1, m_F=1\rangle$. A Feshbach resonance allowed tuning of the scattering length from positive to negative values using a magnetic field. The atoms were cooled and transferred into an optical dipole trap. The scattering length was tuned to a negative value to enable soliton formation. The trapping geometry was deformed adiabatically to a cylindrical geometry, and the vertical trapping beam was switched off to release the BEC into the horizontal waveguide. The soliton was observed to propagate without dispersion over 1.1 mm. The soliton's width remained constant, indicating no dispersion. The soliton's stability was analyzed using a three-dimensional Gross-Pitaevskii energy functional. The results showed that the soliton exists within a narrow window of the parameter $Na/a_{\perp}^{ho}$. The number of atoms allowing soliton formation was found to be between $4.2 \times 10^3$ and $5.2 \times 10^3$, in agreement with the measured number of $6(2) \times 10^3$ atoms. The soliton's size was found to be $l_z \simeq 1.7 \mu m$, below the imaging resolution limit. The study also showed that the soliton's stability could be extended by removing the expulsive axial potential. Future work includes studying soliton coherence and binary collisions.