The Soviet Navashino Shipyard Mordivshchikovo 342 according to a CIA report dated September 1967

An item reported the secured rail and road served Soviet Navashino Shipyard Mordivshchikovo 342 with as geographic coordinates 55.32.97 north and 42.11.18 east located 6 nautical miles south east of Murom, Mordovshchikovo at a former channel of the Oka used for building Volga-Don-1-class dry cargo vessels and perhaps even smaller vessels of a yet unidentified vessel. The shipyard possessed a side-haul marine railways with 2 transverse slipways for which at least 3 cranes were available, a fitting-out quay and 1 fabrication, 5 shop and 32 support buildings.

Source
The report was published on www.archive.org, document number CIA-RDP78T04759A007300010035-9