The rotunda of St. Martin is the largest and oldest preserved rotunda in Prague. It was built in the second half of the 11th century. It has escaped demolition several times in its history. During the Thirty Years’ War it was used as a gunpowder store. The cannonball embedded in the façade to the right of the window is a reminder of the Prussian rampage in 1757. The rotunda is now used for religious purposes by the Vyšehrad ecclesiastical chapter.References:
The Château des ducs de Bretagne (Castle of the Dukes of Brittany) is a large castle located in Nantes. It served as the centre of the historical province of Brittany until its separation in 1941. It was the residence of the Dukes of Brittany between the 13th and 16th centuries, subsequently becoming the Breton residence of the French Monarchy. Today the castle houses the Nantes History Museum.
The restored edifice now includes the new Nantes History Museum, installed in 32 of the castle rooms. The museum presents more than 850 objects of collection with the aid of multimedia devices. The castle and the museum try to offer a modern vision of the heritage by presenting the past, the present and the future of the city. Night-time illuminations at the castle further reinforce the revival of the site. The 500-metre round walk on the fortified ramparts provides views not just of the castle buildings and courtyards but also of the town.