In this paper we present PYTHEAS, an integrated robotic software system that supports autonomous navigation capabilities. These include localization, workspace mapping, path planning and tracking, and obstacle avoidance. PYTHEAS enables mapping of an unknown indoor environment by exploiting sensory information extracted from a laser scanner. Based on this acquired environment representation, the system is able to navigate autonomously in the mapped workspace, avoiding at the same time dynamic obstacles, such as moving persons or other objects. The developed competences are coupled in an integrated system, which can be controlled through a user-friendly interface over the web. Experimental results demonstrate the ability of the developed system to map complicated environments and support navigation in dynamic worlds.