Petrusse Casemates origin goes back to 1644, when the Spaniards reinforced the medieval fortifications. Under the supervision of the Swiss fortress builder Isaac von Treybach, they built - among other defence works-the powerful Beck Bastion, named after Governor Baron Johann von Beck, a native of the city who had played a key role in the Wallenstein affair on the side of the Emperor. Initially this bastion was as high as the adjacent terraces on the right; it was raised to the present level of Constitution Square (the wall is 27 meters high) by Vauban in 1685.
In 1673 the Spaniards erected the so-called 'Ravelin du Pate' to strengthen the defence of the Beck Bastion; this triangular construction is one of the few well-kept fortifications. Marshall de Vauban conferred the present shape to all the Petrusse fortifications and built the 'Small Staircase'. From 1728-29 the Austrians added the 'Bourbon Lock' and the 'Large Staircase' and in 1746 the casemates of the 'Petrusse Battery' (54 gun emplacements).
One century passed and the fortress was enlarged and reinforced: the second ring was extended and the third started, so that Luxembourg became the 'Gibraltar of the North'. By and by, the Petrusse fortifications fell into oblivion and neglect, as their strategic momentum limited itself to the valley. After the dismantling, stipulated by the 1867 London Treaty, they confined themselves to walling up the loopholes and most entrances. In 1933 the Petrusse casemates were opened to the public.References:
Augustusburg Palace represents one of the first examples of Rococo creations in Germany. For the Cologne elector and archbishop Clemens August of the House of Wittelsbach it was the favourite residence. In 1725 the Westphalian architect Johann Conrad Schlaun was commissioned by Clemens August to begin the construction of the palace on the ruins of a medieval moated castle.
In 1728, the Bavarian court architect François de Cuvilliés took over and made the palace into one of the most glorious residences of its time. Until its completion in 1768, numerous outstanding artists of European renown contributed to its beauty. A prime example of the calibre of artists employed here is Balthasar Neumann, who created the design for the magnificent staircase, an enchanting creation full of dynamism and elegance. The magical interplay of architecture, sculpture, painting and garden design made the Brühl Palaces a masterpiece of German Rococo.
UNESCO honoured history and present of the Rococo Palaces by inscribing Augustusburg Palace – together with Falkenlust Palace and their extensive gardens – on the World Heritage List in 1984. From 1949 onwards, Augustusburg Palace was used for representative purposes by the German Federal President and the Federal Government for many decades.
In 1728, Dominique Girard designed the palace gardens according to French models. Owing to constant renovation and care, it is today one of the most authentic examples of 18th century garden design in Europe. Next to the Baroque gardens, Peter Joseph Lenné redesigned the forested areas based on English landscaping models. Today it is a wonderful place to have a walk.