Smart sensors form a foundational layer of intelligent urban infrastructure by delivering continuous, real-time monitoring of environmental, structural, and safety-related conditions. Deployed across key urban zones, these IoT-enabled sensors generate actionable data that supports proactive threat detection and operational optimization. Environmental sensors monitor air quality, noise, temperature, radiation, and other critical factors, triggering alerts when thresholds are exceeded. Structural health sensors embedded in bridges, tunnels, and public buildings detect vibrations, strain, and material fatigue to identify risks early. Public safety sensors contribute to incident prevention through motion detection, vibration sensing, and smart lighting triggers. Water and waste sensors optimize municipal resource management. Edge processing and AI integration enable anomaly detection while reducing network load. All sensor data is securely integrated into centralized Command and Control Centers for unified monitoring and decision support.