St. Mark's Clock Tower in Venice is an early Renaissance building on the north side of the Piazza San Marco, at the entrance to the Merceria. It comprises a tower, which contains the clock, and lower buildings on each side. Both the tower and the clock date from the last decade of the 15th century, though the mechanism of the clock has subsequently been much altered.
It was placed where the clock would be visible from the waters of the lagoon and give notice to everyone of the wealth and glory of Venice. The lower two floors of the tower make a monumental archway into the main street of the city, the Merceria, which linked the political and religious centre (the Piazza) with the commercial and financial centre (the Rialto).
The first clock housed in the tower was built and installed by Gian Paolo and Gian Carlo Rainieri, father and son, between 1496 and 1499, and was one of a number of large public astronomical clocks erected throughout Europe during the 14th and 15th centuries. The clock has had an eventful horological history, and been the subject of many restorations, some controversial.
Stairways (steep and narrow) inside the building give access to the terrace on the roof, passing the clock mechanism on the way. Tours (in Italian, English and French) must be booked in advance.References:
The Château Comtal (Count’s Castle) is a medieval castle within the Cité of Carcassonne, the largest city in Europe with its city walls still intact. The Château Comtal has a strong claim to be called a 'Cathar Castle'. When the Catholic Crusader army arrived in 1209 they first attacked Raymond-Roger Trencavel's castrum at Bèziers and then moved on to his main stronghold at Carcassonne.
The castle with rectangular shape is separated from the city by a deep ditch and defended by two barbicans. There are six towers curtain walls.
The castle was restored in 1853 by the architect Eugène Viollet-le-Duc. It was added to the UNESCO list of World Heritage Sites in 1997.