Thrace is one of the few regions of the Mediterranean in which large numbers of ancient hoards have been discovered, covering extensive time periods. These can be broken into distinct phases. What such agglomerations might look like was quite unknown. Moreover, at least half the total number of known hoards was concentrated in the Central Plain. Whatever the exact reasons for burial, the preponderance of hoards in the Central Plain during the pr-Macedonian phase, as distinct from later periods, made it plain that this was where the power centres of the Odrysian kings should be sought.
Many Thracian princes seem to have minted coins inscribed with their names.
Bergaios may have been such a prince. Excavations began in 1988, under the direction of M.Domaradzki. Within the first few seasons it became clear that Domaradzki had been right. Rare and even new types of silver and bronze coins minted by Odrysian kings appeared among the earliest finds. Analogous types frequently appear on the international antiquities market.