START I was signed on July 31st, 1991, just four months before the Soviet Union collapsed. Its aim was to achieve the reduction and limitation of strategic offensive arms.
The Soviets were obliged to close the entrances of some of their underground structures to any maritime objects, as well as to stop the building of any such structures. This affected Pavlovskoe, and the shelter remained unfinished even though most of the building work had already been completed.
The submarine shelter consists of two main tunnels connected by a network of secondary tunnels, built on three different levels. It was an impressive feat of engineering as the network of tunnels was carved into the cliff rock.
The sheer size of the main tunnels is breathtaking. According to data collected by KFSS, a local urban explorers community, the first tunnel is 21 yards wide and at least 490 yards long. The concrete is about 2 yards thick. At its highest point, it sits 11-13 yards above water level. It is this tunnel that the submarines were supposed to pilot into, half-submerged in water, in the event of a nuclear emergency.
The second tunnel leads into the main hall, which was a space for the main living and working quarters. The main hall is 246 yards long, 9 yards wide, and approximately 12 meters high. In places, stalactite-like icicles hang from the ceiling.
It is hard to tell exactly how large the shelter is as many tunnels have been flooded or blocked off. There are at least 8 entrances and at least 2 ventilation shafts, but there could be more
Pavlovskoe is located within the territory of Pavlovsk – an operational submarine base – so no trespassers are allowed in the area. The territory also evidently has radiation sources as the radiation count is above normal, but the causes are unknown, at least to the public.
