Rostov’s impressive Kremlin was built in the 17th century under the orders of the powerful Metropolitan Iona of Rostov. He wanted the town (which in those days still wielded some power in the region) to have one of the most beautiful Kremlins in the country and to that end he dug deep into the church's coffers to build this imposing fortress.
Nowadays within the Kremlin walls there are numerous museums, although unfortunately most of them are of little interest to foreign visitors. It is however well worth climbing up the Kremlin walls and the bell tower, taking a look in the cathedral and checking out the regular art exhibitions.
In front of the Kremlin is the huge 12th century Dormition of Mary Cathedral, which is in essence a working church - although it should be noted that inside it is undergoing a complete renovation. For a small extra fee you can also climb up the adjacent bell tower for a view over the surrounding area.
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.