This paper presents a motion planning, guidance and control system for an autonomous surface vessel in a practical maritime environment. The motion planning algorithm is based in the angle-guidance fast marching square method and the guidance system is based in the line-of-sight trajectory tracking algorithm. To validate the motion planning algorithm, numerical simulations were carried out to compute the optimal path in a static environment including various obstacles. The guidance and control system were tested with an autonomous surface vehicle tracking a pre-established trajectory including static obstacles. The autonomous surface vehicle is a self-propelled scaled ship model of 2.5 m equipped with sensors and actuators, inertial measurement unit, GNSS positioning system, propulsion DC motors, and wireless communication. From the experiments and numerical simulations, a good agreement was found.