Interesting information by Joseph P Chacko at frontierIndia. com titled “Google Maps Show Indian [Arihant class] Submarines Berthed Alongside” of February 5, 2021:
The photo in question, showing INS Arihant and Arighant together, at right, berthed alongside the pier. (Photo reproduced from idrw . com December 18, 2020.)
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“The [Arihants ] are easily identifiable as the fins are located in the forward with the diving planes are fin mounted. Forward fin permits positioning of missile launchers aft. None of the the Indian conventional submarines have this feature
...Initially [what became INS Arihant] was conceived as SSN based on the [Soviet] Charlie1 classdesign
...However, after the first concept design was made the requirement to make an SSBN post Pokhran 2 (aka II) in May 98, a decision was made to make Arihant as an SSBN.
The objective was achieved with the design collaboration with Rubin design bureau in St Petersburg.” Much more.