Tsarevets Hill is located in Veliko Tarnovo. It is the main fortress of medieval Tarnovgrad, in the center of which rise the royal and patriarchal palaces. The first fortified settlement, built on Tsarevets Hill, dates from the Late Chalcolithic (4200 BC). It continued its development during the Late Bronze Age (IV - II century BC) and the Iron Age (XIII - I century BC), when its inhabitants were the Thracians. In the V - VII century on the site of the Thracian settlement is Zikideva - the largest fortified city of the Byzantine Empire in the province of Lower Moesia. It was destroyed during the Avar-Slavic invasions in the 7th century. In the 9th century, an old Bulgarian fortress appeared on the site of the early Byzantine fortress, which developed and grew during the First Bulgarian State and especially during the Byzantine rule. Archaeological excavations in Tsarevets began in 1886 by the Czech scientist Karel Škorpil and continued in 1893 and 1900, but the lack of system and organization gives them a partial character. After 1905, the excavations undertaken by the revived archeological society in Tarnovo were carried out partially and intermittently due to lack of funds. In 1930, excavations were made that preceded the restoration of the Baldwin Tower. In 1932-1934 the first gate from the main entrance was restored, and in 1935 a study of the water supply of Tsarevets and Trapezitsa was made. After 1946, systematic archeological excavations of the palace of the Bulgarian kings from the Second Bulgarian State began. In 1958 and 1959 the then Regional Historical Museum began researching the fortress system of Tsarevets.