Indian Railways has begun the deployment of its most advanced indigenous train safety system, Kavach 4.0, with the first operational rollout on the Mathura–Kota stretch of the high-traffic Delhi–Mumbai corridor.The launch marks a key milestone in the modernisation of railway safety infrastructure and aligns with the government's Atmanirbhar Bharat vision. Kavach—meaning “armour”—is an Automatic Train Protection (ATP) system developed entirely in India. The latest 4.0 version includes upgraded features designed to minimise human error and enhance the overall security of railway operations.Kavach 4.0 operates using Radio Frequency Identification (RFID) tags installed every kilometre along the railway line and at signal points. These allow real-time tracking of train positions. The system is supported by an extensive network of telecom towers and fibre optic cables that ensure seamless data exchange between locomotives and central control centres.Notably, the technology functions reliably even in poor weather conditions such as dense fog. Loco pilots receive vital information directly on their cabin dashboards, reducing dependence on external signals. It is integrated with the braking system, enabling automatic emergency braking when required.Kavach 4.0 is built to comply with Safety Integrity Level 4 (SIL4)—the highest global safety standard—and has been approved for trains running at speeds up to 160 kmph. Its implementation involves infrastructure similar to a dedicated telecom network, due to the significant installation of fibre cabling and communication towers.To date, Indian Railways has installed the system across over 4,000 km of track, covering 708 stations and 1,107 locomotives. The backbone includes 5,856 km of optical fibre and 619 telecom towers. Over 30,000 railway personnel have been trained to ensure effective implementation and operation of the system across the network.