This paper presents a research project that consists in the analysis, design, development and demonstration of a mobility aid for partially sighted/blind people, intended to allow them a safe and autonomous mobility in urban scenarios. Some mobility aids exist, mostly based on consumer GPS receivers, but they are not completely suitable or present some limitations. To overcome these limitations, we propose a system in which the user may move on a ground-level virtual path, which may be followed through the use of an electronic device mounted on a traditional white cane (smart cane). The device is able to detect the virtual path and to signal to the users, by means of vibration, that they are moving on a safe path. The smart cane also interacts through a Bluetooth link with a mobile device, which manages different navigation functionalities. Vocal information are sent by the mobile device through a wireless link to an earpiece worn by the user. The stick is equipped with a basic input interface (mini-joystick and slider) which allows the control of the main and frequently used functions of the system. The project, still in progress, plans the final installation of a demonstrator on the Walls of Lucca city, for a final validation by the users.