Ancient Vyshgorod was first and foremost a powerful fortress, which, during the military threat, had to protect its inhabitants not only from the city itself, but also from the neighborhood (similar to Western European castles). Therefore, great attention was devoted to the creation and maintenance of defense structures.
The territory of Vyshhorod during the time of Kyivan Rus consisted of fortified Dytyntets and roundabout town, as well as an open outskirts (so called “posad”).
Even P. Svin’in, who visited Vyshhorod in 1825, reflected the configuration of fortifications very accurately, describing two lines of defensive structures, almost parallel to the slope itself.
According to the local priest’s words, the remains of the third building were still visible in the forest, a half miles from the church!
V.Antonovich counted six concentric lines of shafts, that surrounded the settlement, obviously, taking the differences of heights of natural origin for fortifications.
In general, two lines of fortifications, described by researchers of the nineteenth century, have survived to this day (best of all – in the courtyard of the church of Boris and Gleb).
An open question remains about the existence of the third line of defense, which could protect the posad on a steep slope of the terrace, because this line was completely or almost completely destroyed by ravines.
Obviously, in the tenth century fortifications already existed, this is visible from the very root of the word “grad”, which means “city”, from which the name of the town comes from. It is known, that this term in old times meant not only the city as a whole, that is, a settlement with a city structure, and, above all, a settlement, surrounded by defensive structures.
Defensive structures of Vyshhorod are mentioned in the chronicle three times.
Under 1115, the chronicle’s author describes, how the Vishgorod inhabitants watched the transfer of the tombs of Boris and Gleb to a new church from the city walls and barbarques.
Dytynets was a virtually impregnable fortress: at the time of the first archaeological research in the 1930s, the elevation drop from the bottom of the ditch to the top of the shaft at some sites was about 10 m.
The cuts of the shafts, performed by archaeologists in different years, showed, that the structures from the oak, and in one case – from the birch, were used for its construction.
The different nature of the tree-earthen structures constitutes a reorganization of fortifications, and also reflects the dynamics of the city's development.
In addition, the design features of the shaft depended on the specific features of each individual site, on which they were built. These trends are typical for other cities of the Middle Dnieper, such as Pereyaslav or Belgorod. Researcher P. Rappoport believed, that birch logs, excavated in the 1930s, appeared in the XI century, while the appearance of solid oak constructions was associated with the restoration of the shaft in the XII century.
The construction and repair of defense structures was carried out by individual specialists – “gorodnics” (builders of fences), which are mentioned in the “Statute” of Vladimir Monomakh and the lives of saints Boris and Gleb.
Most likely, these monuments of writing were created in Vyshgorod and therefore kept unique data on local “gorodnics”, leaving, unlike the builders of fences of other cities, their names.
Scientists see associations of “gorodnics”, in particular from Vyshgorod, as the earliest “craft corporations”. Obviously, they were connected with the princely administration and occupied a high social position.