Tsarevets is a medieval stronghold located on a hill with the same name in Veliko Tarnovo in northern Bulgaria. It served as the Second Bulgarian Empire's primary fortress and strongest bulwark between 1185 and 1393, housing the royal and the patriarchal palaces, and it is also a popular tourist attraction.
The hill has evidence of human presence from the 2nd millennium BC and was settled in the 4th century. After the Bulgarian Rebellion, it became the empire's key fortress, comparable to Rome and Constantinople. In 1393, it fell to Ottoman forces, marking the Bulgarian Empire's demise.
The fortress has three entrances, with a central complex featuring a throne hall, castle church, and king's chamber. Restoration started in 1930 and was completed in 1981. The stronghold, surrounded by thick walls and three gates, housed kings Petar, Asen, Kaloyan, and Ivan Asen II. The palace complex included a fortified wall, towers, and entrances. The patriarchate, at the hill's top, has the Cathedral of the Ascension of the Lord.
Baldwin's Tower, a modern reconstruction in the southeastern part, commemorates Latin Emperor Baldwin I's death. During the Middle Ages, the hill had residential buildings, workshops, churches, and monasteries. Archaeologists found 400 buildings, 22 churches, and 4 monasteries. Execution Rock, where traitors were pushed into the Yantra River, is also located here; Patriarch Joachim was executed in 1300.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.