Almarestäkets castle was built in the 1100s to protect the Sigtuna and Uppsala cities. It was also called as St. Erik's castle after Eric IX. Throughout the Middle Ages there was a struggle between the Crown and Church who can control the castle.
The castle was first mentioned in the late 1300s. In 1440 got Archbishop Nicolaus Ragvaldi permission to build a new castle, which was completed about ten years later. In the 1510s troubles Almarestäkets was in possession of Bishop Gustav Trolle between 1516-17. The castle was sieged by his main enemy Sten Sture the Younger in 1517. Archbishop Gustav Trolle locked himself in there to avoid trial, and the Swedish government demanded and carried out the demolition of the fortress. The procedure was formally unauthorized because at the time State property was to be separate from Church property. As a revenge for this and other perceived injustices, Trolle, assisted by the Danish King Christian II, took revenge in the Stockholm Bloodbath of 1520.
Today there are visible traces of castle foundations with potholes filled with stone and occasional bricks.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.