India developing secretive nuclear submarine base 

India is approaching the final stages of a highly classified naval facility near Rambilli, a coastal village in Andhra Pradesh located around 50 kilometers south of Visakhapatnam, home to the Eastern Naval Command. 

The base, part of the covert Project Varsha, represents a major step in enhancing India’s maritime security posture, according to reports by the Times of India.
What makes this facility unique is not just its strategic location on the Bay of Bengal—but what lies beneath it.
The Rambilli base is being constructed with a network of underground tunnels and submarine pens, specifically designed to house India's nuclear-powered ballistic missile submarines (SSBNs). These hidden structures will allow submarines to deploy into deep waters without being tracked by surveillance satellites, particularly those operated by China. From there, they can quietly move toward key strategic routes such as the Malacca Strait for deterrent patrol missions.
According to a senior defense official cited in the report, the first phase of the Rambilli project is nearly finished and is expected to be operational by 2026. Once commissioned, the facility can be expanded in stages, mirroring the modular development approach seen at Karwar under Project Seabird.
The development of Rambilli has spanned more than a decade, with progress slowed at times by technical challenges, environmental concerns, and logistical complexities.
Like China's fortified naval stronghold on Hainan Island, Rambilli is designed for stealth. The natural underwater depth in the region offers an ideal cover, allowing submarines to maneuver in and out without detection—an essential feature for maintaining the secrecy and effectiveness of a nuclear second-strike capability.
While India’s undersea nuclear deterrent is still in its formative years, the completion of this base signals a significant strategic leap. Protecting the country’s sea-based nuclear assets is seen as vital to ensuring credible deterrence in an increasingly competitive Indo-Pacific security environment.