Nitra castle was built in the 11th century on the place of an earlier fort. The core of the castle is St. Emmeram's Cathedral with the Bishop's residence, with several different parts. The oldest surviving part is the Romanesque Church of St. Emmeram from the 11th century. The other two parts of the cathedral are the originally Gothic Upper Church from the 14th century, and the Lower Church from the 17th century. Vazil´s Tower is another remaining part of the medieval fortification. According to a legend, Vazil, king Stephen´s nephew, was imprisoned in a dungeon supposed to be in the Tower´s underground.
The originally Gothic Bishop's Palace got its present Late Baroque appearance in the 18th century. There are also surviving parts of the castle fortifications, the majority of which were created in the 16th and 17th centuries and smaller part from the Middle Ages. The church is currently being remodeled.
References:The Roman Theatre of Mérida is a construction promoted by the consul Vipsanius Agrippa in the Roman city of Emerita Augusta, capital of Lusitania (current Mérida). It was constructed in the years 16 to 15 BCE. One of the most famous and visited landmarks in Spain, the Roman Theatre of Mérida is regarded as a Spanish cultural icon and was chosen as one of the 12 Treasures of Spain.
The theatre has undergone several renovations, notably at the end of the 1st century or early 2nd century CE (possibly during the reign of Emperor Trajan), when the current facade of the scaenae frons was erected, and another in the time of Constantine I (between 330 and 340), which introduced new decorative-architectural elements and a walkway around the monument. Following the theatre"s abandonment in Late Antiquity, it was slowly covered with earth, with only the upper tiers of seats (summa cavea) remaining visible.