A navigation system with a capability of estimating positions of the platform vehicle and recognized landmarks using satellite information and camera measurements is disclosed. One aspect is to represent a landmark by one or few representative features by executing image recognition and feature extraction to find representative features inside the recognized landmark. Another aspect is to re-identify the recognized landmarks in the landmark database correlating the landmark attributes obtained by image recognition and mathematical feature characteristics obtained by feature extraction with the corresponding data in the landmark database. A further aspect is to enhance navigation accuracy through the Kalman filter architecture with additional imagery measurements of landmarks whose positions are known or previously estimated. According to the aspects noted above: (1) navigation accuracy improves with augmented imagery measurements; (2) a database of recognizable landmark attributes and associated feature characteristics can be created in real-time; (3) by re-visiting the same landmarks, navigation accuracy improves and the landmark database will be re-calibrated and augmented with new landmark data.