Ahrensbök Charterhouse was a former Carthusian monastery or charterhouse established in 1397. The estates with which it was endowed reached as far as Scharbeutz on the Bay of Lübeck.
During the Reformation the monastery was secularised, and with its estates fell into the hands of John II, Duke of Schleswig-Holstein-Sonderburg, in 1584, who had the buildings demolished.
The building materials were used between 1593 and 1601 for the construction of the castle in Ahrensbök, Schloss Hoppenbrook, which was the principal residence between 1623 and 1636 of the ruler of the newly formed Duchy of Schleswig-Holstein-Sonderburg-Plön while Duke Joachim Ernst I's new castle in Plön was under construction. Once Schloss Plön was finished, the ducal residence was moved there from Ahrensbök, leaving Schloss Hoppenbrook as a secondary residence.
After the death there in 1740 of Duchess Juliane Luise, widow of Joachim Frederick, Duke of Schleswig-Holstein-Sonderburg-Plön, Schloss Hoppenbrook was demolished. The Rathaus of Ahrensbök now stands on its site, in a park in which ditches from the previous castle complex can still be made out.
The only surviving building from the time of the Carthusians is the Brick Gothic St. Mary's church - Marienkirche - which in fact was begun in the first quarter of the 14th century and thus predates the monastery itself: when the charterhouse was established it was taken over for use as the monastery church. It was extended several times, and in 1400 the polygonal quire was added. The tower, with an inscribed sandstone tablet over the portal, was not added until 1761.References:
Roman Walls of Lugo are an exceptional architectural, archaeological and constructive legacy of Roman engineering, dating from the 3rd and 4th centuries AD. The Walls are built of internal and external stone facings of slate with some granite, with a core filling of a conglomerate of slate slabs and worked stone pieces from Roman buildings, interlocked with lime mortar.
Their total length of 2117 m in the shape of an oblong rectangle occupies an area of 1.68 ha. Their height varies between 8 and 10 m, with a width of 4.2 m, reaching 7 m in some specific points. The walls still contain 85 external towers, 10 gates (five of which are original and five that were opened in modern times), four staircases and two ramps providing access to the walkway along the top of the walls, one of which is internal and the other external. Each tower contained access stairs leading from the intervallum to the wall walk of town wall, of which a total of 21 have been discovered to date.
The defences of Lugo are the most complete and best preserved example of Roman military architecture in the Western Roman Empire.
Despite the renovation work carried out, the walls conserve their original layout and the construction features associated with their defensive purpose, with walls, battlements, towers, fortifications, both modern and original gates and stairways, and a moat.
Since they were built, the walls have defined the layout and growth of the city, which was declared a Historical-Artistic Ensemble in 1973, forming a part of it and becoming an emblematic structure that can be freely accessed to walk along. The local inhabitants and visitors alike have used them as an area for enjoyment and as a part of urban life for centuries.
The fortifications were added to UNESCO"s World Heritage List in late 2000 and are a popular tourist attraction.