The topographic survey was conducted by Y.A. Savelyev and A.V. Kleshnin, members of the Kharkiv Regional Branch of the “Children of the Underground” Charitable Foundation, in October 2014.
The building consists of five interconnected basement rooms with arched ceilings constructed of red brick set in lime mortar. Two of them are occupied by a café, while the remaining three house components of the water supply and heating systems for the Kharkiv College of Construction, Architecture, and Design.
The original floor of these rooms has been filled with soil to a height of up to 2 m. As a result, the current height of the basement ranges from 2.5 to 3.5 m. The width ranges from 3.4 to 4.5 m. In one of the rooms, elements of an old heating system were discovered: the remains of a furnace structure and niches in the vault through which hot air rose into the walls and heated the rooms above ground.
In three places, the basement rooms were divided by new walls as early as the second half of the 20th century. In one instance, a hole was cut through the vault to accommodate a column supporting the first-floor slab. In the southern end wall of the basement section facing Kvitky-Osnov’yanenka Street, a door bricked up with lime mortar is clearly visible; it presumably led to a coal pit located outside the building’s perimeter.
Adjacent to the aforementioned basement section of the building on the side facing Kvitky-Osnov’yanenka Street is a system of six underground galleries, also constructed of red brick set in lime mortar and later plastered. The galleries are 2.25 m high and 2.13 m wide. The floor is earthen. By the time the research began, the entrance gallery had been almost completely filled in with earth and construction debris—to a depth of 5–6 m. The galleries were constructed using the cut-and-cover method and were laid at varying slopes, which may be related to the varying depths of the basements of the buildings that these galleries connected. In five cases, the galleries end with surface-level blockages (indicating a breach in the vault). In one case, there is a section of unfinished construction that is not closed off by an end wall, allowing us to visually determine the thickness of the vault to be 0.75 bricks.
There are water marks on the walls, leading us to conclude that this underground passage was once flooded to a depth of more than 1.5 meters.
At the points where the tunnels intersected, metal hooks had been driven into the vaulted section; small porcelain insulators, similar to those found in the underground structure near 23 Rymars’ka Street, were discovered on the floor, along with 23 electrical wiring components.
The excavated material consists mainly of household waste from the mid-20th century and the second half of the 20th century. This is primarily due to the fact that this underground facility was used as a bomb shelter for civilians and military personnel from 1941 to 1943, as indicated by both oral accounts from Kharkiv’s older residents and the finds — the remains of a Mosin rifle (model 1891–1930) and a radio.
Thus, based on the information gathered to date and on-site surveys of this underground structure, it can be concluded that the system of underground galleries—constructed in the late 18th century using a closed-tunnel method and adjoining the basements of the Gostiny Dvor— originally served two functions: as a passageway (connecting the basements of at least five merchant properties and the Assumption Cathedral) and as a storage facility (a wine cellar). In 1941, while preparing a network of civil defense facilities in Kharkiv to shelter the civilian population from German bombing raids, these underground galleries were inspected and deemed suitable for use in this capacity.
