The Bonn Minster (Bonner Münster) is one of Germany's oldest churches, having been built between the 11th and 13th centuries. At one point the church served as the cathedral for the Archbishopric of Cologne.
Castra Bonnensia was a fortress on the site of current Bonn built by the Romans in the 1st century AD. It survived the breakup of the Roman Empire as a civilian settlement, and in the 9th century it became the Frankish town of Bonnburg.
Around 235 AD, two Christian Roman soldiers stationed in Castra Bonnensia, Cassius and Florentius, were martyred for their faith. Tradition has it that a small memorial shrine was built over their graves in the 4th century by St. Helen, mother of Constantine. There is no surviving evidence of this first structure, but archaeological excavations have shown that the basilica stands on the site of a Roman temple and necropolis.
The original memorial hall was expanded into a larger church in the 6th and 7th centuries, and many people were buried near the martyrs inside and outside the building. Further extensions were carried out in the 8th century.
Around 1050 the church was demolished and construction began on the present Romanesque building, which dates from the 11th to 13th centuries. By the end of this period Bonn had grown in importance, becoming the capital of the Electorate and Archbishopric of Cologne, which was then a sovereign state. The new basilica appeared in the city's coat of arms. In 1643, Cassius and Florentius were officially declared the patron saints of the city of Bonn.
The basilica suffered significant damage in 1583-89, 1689, and in World War II, but each time it was fully restored. In 1956, the Bonner Münster was granted the status of Papal Minor Basilica.
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.